1 00:00:00,040 --> 00:00:02,460 The following content is provided under a Creative 2 00:00:02,460 --> 00:00:03,970 Commons license. 3 00:00:03,970 --> 00:00:06,910 Your support will help MIT OpenCourseWare continue to 4 00:00:06,910 --> 00:00:10,660 offer high-quality educational resources for free. 5 00:00:10,660 --> 00:00:13,460 To make a donation or view additional materials from 6 00:00:13,460 --> 00:00:17,390 hundreds of MIT courses, visit MIT OpenCourseWare at 7 00:00:17,390 --> 00:00:18,640 ocw.mit.edu. 8 00:00:28,190 --> 00:00:35,200 PROFESSOR: Where we left it at the end of last time was the 9 00:00:35,200 --> 00:00:38,080 mechanism for poverty trap that [INAUDIBLE] 10 00:00:38,080 --> 00:00:42,530 explained, and that was kind of a workhorse of development 11 00:00:42,530 --> 00:00:45,540 economics for many years, since the 1950s, might 12 00:00:45,540 --> 00:00:48,650 actually, surprisingly, not be at play. 13 00:00:48,650 --> 00:00:54,510 In that, number one, the effect of your calorie 14 00:00:54,510 --> 00:00:59,320 consumption on your productivity in the immediate 15 00:00:59,320 --> 00:01:02,650 next few days is probably not large enough. 16 00:01:02,650 --> 00:01:06,490 And, perhaps as a consequence, or perhaps just because they 17 00:01:06,490 --> 00:01:09,140 have other things to do with their money, we don't see the 18 00:01:09,140 --> 00:01:14,160 poor also consuming as much as they can. 19 00:01:14,160 --> 00:01:18,790 And therefore, we don't see a very high elasticity of food 20 00:01:18,790 --> 00:01:21,790 consumption with respect to wages. 21 00:01:21,790 --> 00:01:25,140 So if we don't have a very high elasticity of wages with 22 00:01:25,140 --> 00:01:28,560 respect to consumption, and we don't have a very high 23 00:01:28,560 --> 00:01:32,020 elasticity of consumption with respect to wages, then we are 24 00:01:32,020 --> 00:01:35,360 not going to get a very highest elasticity of wages 25 00:01:35,360 --> 00:01:37,780 tomorrow with respect to wages yesterday. 26 00:01:37,780 --> 00:01:40,990 And therefore, the whole thing of I am poor because I am 27 00:01:40,990 --> 00:01:45,900 poor, based on how much food I can consume 28 00:01:45,900 --> 00:01:47,730 is not really there. 29 00:01:47,730 --> 00:01:51,060 So on the one hand, you could say fine, that great. 30 00:01:51,060 --> 00:01:53,470 It means we can start focusing on other programs, and 31 00:01:53,470 --> 00:01:55,890 nutrition is not really an issue. 32 00:01:55,890 --> 00:01:58,320 And for some people, that has been the conclusion. 33 00:01:58,320 --> 00:02:04,360 For example, on Tuesday, we showed some graphs coming from 34 00:02:04,360 --> 00:02:09,270 the paper by Angus Deaton and Jean Dreze about the fact that 35 00:02:09,270 --> 00:02:13,130 people are consuming less and less calories in India. 36 00:02:13,130 --> 00:02:16,060 So they are becoming richer, so they are moving along the 37 00:02:16,060 --> 00:02:17,760 angle curve. 38 00:02:17,760 --> 00:02:20,680 And that would make them consume more, 39 00:02:20,680 --> 00:02:22,450 everything else equal. 40 00:02:22,450 --> 00:02:24,920 But the thing is, not everything else is equal. 41 00:02:24,920 --> 00:02:27,590 And at the same time, we have the angle of curve 42 00:02:27,590 --> 00:02:29,370 shifting to the right. 43 00:02:29,370 --> 00:02:31,840 So that it's a swimming upstream movement, where 44 00:02:31,840 --> 00:02:34,590 you're trying to go up the angle curve, but the angle 45 00:02:34,590 --> 00:02:37,050 curve is shifting right, so you end up actually consuming 46 00:02:37,050 --> 00:02:43,050 less, fewer calories than you would otherwise consume, 47 00:02:43,050 --> 00:02:47,090 So for some people in India, this is a sign that there's 48 00:02:47,090 --> 00:02:50,790 much more poverty than the official 49 00:02:50,790 --> 00:02:52,610 statistics are saying. 50 00:02:52,610 --> 00:02:55,890 Because if we define poverty as not having enough to eat, 51 00:02:55,890 --> 00:02:58,400 then we have more and more people who in fact don't have 52 00:02:58,400 --> 00:03:00,380 enough to eat. 53 00:03:00,380 --> 00:03:03,030 But what is strange is that if we look at the other things 54 00:03:03,030 --> 00:03:06,070 that people consume, and we measure poverty in this way, 55 00:03:06,070 --> 00:03:09,360 which is, if you look at the entire budget, are you below-- 56 00:03:09,360 --> 00:03:11,830 are you someone who consumes less than a dollar a day per 57 00:03:11,830 --> 00:03:15,180 capita, of 16 rupees a day, because it's India? 58 00:03:15,180 --> 00:03:16,210 And you don't find that. 59 00:03:16,210 --> 00:03:21,400 You find that actually there are fewer and fewer people who 60 00:03:21,400 --> 00:03:22,830 are below a dollar a day. 61 00:03:22,830 --> 00:03:23,940 There is still a number. 62 00:03:23,940 --> 00:03:25,190 It's about 13%. 63 00:03:25,190 --> 00:03:27,330 but it's certainly going down. 64 00:03:27,330 --> 00:03:30,340 So it has to be that people exercise a choice 65 00:03:30,340 --> 00:03:32,810 not to eat as much. 66 00:03:32,810 --> 00:03:38,856 So Deaton and Dreze who wrote this paper and documented the 67 00:03:38,856 --> 00:03:42,680 decline in calorie consumption in India, have one 68 00:03:42,680 --> 00:03:43,850 explanation. 69 00:03:43,850 --> 00:03:47,540 And their explanation is that people's need for calories has 70 00:03:47,540 --> 00:03:51,950 gone down because they are less ill, they have fewer 71 00:03:51,950 --> 00:03:54,865 children, they are doing less intense physical work. 72 00:03:54,865 --> 00:03:57,560 A lot of people have moved to the urban areas. 73 00:03:57,560 --> 00:03:59,900 So it's just they eat less because they 74 00:03:59,900 --> 00:04:01,780 need less of the strength. 75 00:04:01,780 --> 00:04:05,370 And therefore we have nothing to worry about, in a sense. 76 00:04:05,370 --> 00:04:08,380 The fact that people are eating less is, in a sense, a 77 00:04:08,380 --> 00:04:15,840 sign of success of India's economic growth. 78 00:04:15,840 --> 00:04:19,380 But if it were the case, then we should find that the 79 00:04:19,380 --> 00:04:23,080 nutritional status of people would be adequate. 80 00:04:23,080 --> 00:04:24,920 Defined in more objective terms. 81 00:04:24,920 --> 00:04:28,190 Not the calories you're consuming, but what is your 82 00:04:28,190 --> 00:04:30,660 weight, what is your height. 83 00:04:30,660 --> 00:04:32,580 Whether you're anemic or not. 84 00:04:32,580 --> 00:04:35,400 We should find an improvement in that. 85 00:04:35,400 --> 00:04:38,100 Because, to the extent that people are getting richer, 86 00:04:38,100 --> 00:04:40,240 they should want a little bit of improvement in their 87 00:04:40,240 --> 00:04:41,790 nutritional status. 88 00:04:41,790 --> 00:04:44,700 And what is striking and surprising, which is why they 89 00:04:44,700 --> 00:04:50,240 might be hidden traps is that by all accounts, in India in 90 00:04:50,240 --> 00:04:53,710 particular but in other places as well, people are still not 91 00:04:53,710 --> 00:04:55,440 very well-nourished. 92 00:04:55,440 --> 00:04:58,880 And it is more a matter of there is some 93 00:04:58,880 --> 00:05:02,380 undernourishment, which is people are not eating that 94 00:05:02,380 --> 00:05:03,790 many calories. 95 00:05:03,790 --> 00:05:08,470 And also, maybe something that people referred to as hidden 96 00:05:08,470 --> 00:05:12,110 hunger, and you can think about as malnutrition. 97 00:05:12,110 --> 00:05:15,270 Which is even the condition of having enough calories if 98 00:05:15,270 --> 00:05:19,540 people are not getting enough of the other micronutrients 99 00:05:19,540 --> 00:05:22,770 that they need-- for example, anemia. 100 00:05:22,770 --> 00:05:26,980 So here is a number for India. 101 00:05:26,980 --> 00:05:35,440 33% of men and 36% of women have a BMI below 18.5. 102 00:05:35,440 --> 00:05:40,750 And meanwhile, iron deficiency anemia affects maybe something 103 00:05:40,750 --> 00:05:44,230 like a billion people worldwide. 104 00:05:44,230 --> 00:05:48,590 And iron deficiency anemia means that people are in fact 105 00:05:48,590 --> 00:05:52,840 less strong, because the ability of their body or their 106 00:05:52,840 --> 00:05:56,940 blood to process the oxygen is limited. 107 00:05:56,940 --> 00:06:00,700 Because we process the oxygen with other blood cells in our 108 00:06:00,700 --> 00:06:02,710 body, the hemoglobin in our blood. 109 00:06:02,710 --> 00:06:04,620 And if we don't have enough of that, we're not very good at 110 00:06:04,620 --> 00:06:06,440 processing the oxygen. 111 00:06:06,440 --> 00:06:08,760 So you put people on the treadmill that are anemic, and 112 00:06:08,760 --> 00:06:11,680 they are not able to make it go as far. 113 00:06:14,740 --> 00:06:18,370 So we have here a puzzle that, on the one hand, we don't see 114 00:06:18,370 --> 00:06:21,160 people appearing to be hungry for calories. 115 00:06:21,160 --> 00:06:29,750 In fact, in China we see this Jensen, Miller evidence, which 116 00:06:29,750 --> 00:06:30,760 goes the opposite way. 117 00:06:30,760 --> 00:06:33,030 Which is, you make the cheaper source of calories cheaper, 118 00:06:33,030 --> 00:06:36,670 and people eat fewer calories, at least in one region. 119 00:06:36,670 --> 00:06:41,620 And yet, they seem to be not very well-nourished. 120 00:06:41,620 --> 00:06:44,410 so what could be going on? 121 00:06:47,620 --> 00:06:49,620 Let me start with you, your reason. 122 00:06:49,620 --> 00:06:50,610 And I will present it. 123 00:06:50,610 --> 00:06:53,340 AUDIENCE: Their diets are very narrow and the 124 00:06:53,340 --> 00:06:54,280 same all the time. 125 00:06:54,280 --> 00:06:58,192 So they don't really correlate what they eat to-- 126 00:06:58,192 --> 00:07:00,148 It's just kind of an informational thing. 127 00:07:00,148 --> 00:07:02,430 They don't realize what kinds of nutrients they actually 128 00:07:02,430 --> 00:07:04,304 need, so they just have what tastes good or what they're 129 00:07:04,304 --> 00:07:05,530 used to eating. 130 00:07:05,530 --> 00:07:07,150 PROFESSOR: So it could be, for example-- 131 00:07:07,150 --> 00:07:09,380 I'm just rephrasing for everyone, because you speak in 132 00:07:09,380 --> 00:07:11,980 this very nice and soft tone-- 133 00:07:11,980 --> 00:07:16,210 It could be that they don't have the information that 134 00:07:16,210 --> 00:07:18,560 nutrition affects your strength. 135 00:07:18,560 --> 00:07:21,630 In fact, you proposed one very specific theory for that, 136 00:07:21,630 --> 00:07:25,060 which is, if you've never experimented because you've 137 00:07:25,060 --> 00:07:28,670 always eaten same thing, then you might not know what would 138 00:07:28,670 --> 00:07:31,050 happen outside of your normal range. 139 00:07:31,050 --> 00:07:33,360 So that would be one reason why you don't have the 140 00:07:33,360 --> 00:07:34,610 information. 141 00:07:36,545 --> 00:07:38,533 AUDIENCE: And then when someone, or maybe the 142 00:07:38,533 --> 00:07:42,012 government, suggests a different diet, or replacing 143 00:07:42,012 --> 00:07:46,485 what people are normally used to eating, they're not really 144 00:07:46,485 --> 00:07:48,473 willing to take that advice. 145 00:07:48,473 --> 00:07:49,964 And so that can-- 146 00:07:49,964 --> 00:07:53,443 they'll just continue eating [INAUDIBLE] 147 00:07:53,443 --> 00:07:54,934 just normally eating. 148 00:07:54,934 --> 00:07:58,935 Their diet is based mainly on grains and rice. 149 00:07:58,935 --> 00:08:01,531 And if someone in the government says, well, there's 150 00:08:01,531 --> 00:08:02,340 a shortage of that. 151 00:08:02,340 --> 00:08:05,250 Maybe you should supplement more vegetables for it. 152 00:08:05,250 --> 00:08:09,130 Then they aren't very willing to switch. 153 00:08:11,910 --> 00:08:14,050 PROFESSOR: One reason why your information might be limited 154 00:08:14,050 --> 00:08:16,350 is that even when you get a source of 155 00:08:16,350 --> 00:08:17,590 information from outside-- 156 00:08:17,590 --> 00:08:19,700 for example, the government-- tells you, you 157 00:08:19,700 --> 00:08:21,380 should eat your vegetable. 158 00:08:21,380 --> 00:08:26,450 You should eat these kinds of cereals rather than those 159 00:08:26,450 --> 00:08:27,180 kinds of cereals. 160 00:08:27,180 --> 00:08:32,140 You should replace some rice with pulses, or some rice with 161 00:08:32,140 --> 00:08:36,500 cereals, people are reluctant to do it. 162 00:08:36,500 --> 00:08:42,460 And why would we think that people are reluctant to follow 163 00:08:42,460 --> 00:08:45,518 this information from the government? 164 00:08:45,518 --> 00:08:46,014 AUDIENCE: A bunch of reasons. 165 00:08:46,014 --> 00:08:49,982 One might be a variety of foods might not be available 166 00:08:49,982 --> 00:08:50,974 in that region. 167 00:08:50,974 --> 00:08:53,950 And also, a lot of those things are more expensive. 168 00:08:53,950 --> 00:08:56,926 So the cheaper things are very carb-heavy things, which is 169 00:08:56,926 --> 00:08:58,414 quite filling. 170 00:08:58,414 --> 00:09:02,910 So you might not choose to go with vegetables [INAUDIBLE]. 171 00:09:02,910 --> 00:09:03,270 PROFESSOR: Right. 172 00:09:03,270 --> 00:09:04,530 So there are two reasons, two 173 00:09:04,530 --> 00:09:05,770 possibilities in what you said. 174 00:09:05,770 --> 00:09:07,890 The first one is a chicken and egg problem. 175 00:09:07,890 --> 00:09:11,200 Because if no one eats spinach in a place-- 176 00:09:11,200 --> 00:09:14,280 and spinach is a great thing-- 177 00:09:14,280 --> 00:09:16,410 but if no one eats it, it's just not available, and 178 00:09:16,410 --> 00:09:18,250 therefore you cannot try it out. 179 00:09:18,250 --> 00:09:19,690 What was the second one, excuse me? 180 00:09:19,690 --> 00:09:22,045 AUDIENCE: The second one is that the cheaper food is 181 00:09:22,045 --> 00:09:25,109 generally more carb-heavy, and so it's quite filling, and you 182 00:09:25,109 --> 00:09:29,252 might choose to buy that over vegetables which are much more 183 00:09:29,252 --> 00:09:30,750 expensive than the rest of the food. 184 00:09:30,750 --> 00:09:31,175 PROFESSOR: Right. 185 00:09:31,175 --> 00:09:33,703 And the second one could be a matter of costs. 186 00:09:33,703 --> 00:09:35,675 AUDIENCE: And I think that the benefit of nutrient intakes 187 00:09:35,675 --> 00:09:37,154 are over the long-term. 188 00:09:37,154 --> 00:09:39,619 So if you're taking a small iron tablet, the next day, 189 00:09:39,619 --> 00:09:42,084 miraculously you're not going to perform better. 190 00:09:42,084 --> 00:09:45,042 But over the long-term, you might see smaller 191 00:09:45,042 --> 00:09:46,030 improvements. 192 00:09:46,030 --> 00:09:46,410 PROFESSOR: Right. 193 00:09:46,410 --> 00:09:49,420 So it could be that if is difficult to learn. 194 00:09:49,420 --> 00:09:52,880 So for example, one thing that could happen is that someone 195 00:09:52,880 --> 00:09:56,050 from outside, very well-meaning, say you should 196 00:09:56,050 --> 00:10:00,830 really eat iron-fortified flour instead of 197 00:10:00,830 --> 00:10:02,710 your regular flour. 198 00:10:02,710 --> 00:10:04,020 And you try. 199 00:10:04,020 --> 00:10:07,090 And then, after one week, you don't feel like Popeye. 200 00:10:07,090 --> 00:10:10,480 It's not that things have dramatically changed. 201 00:10:10,480 --> 00:10:14,550 And in fact, if I put you on a treadmill and I ask you to 202 00:10:14,550 --> 00:10:16,280 perform an exercise, I will know 203 00:10:16,280 --> 00:10:19,130 that you are 10% stronger. 204 00:10:19,130 --> 00:10:20,820 But this is not something-- 205 00:10:20,820 --> 00:10:28,040 if you are 10% stronger the next month, are you going to 206 00:10:28,040 --> 00:10:30,770 be able to really see the difference or not? 207 00:10:30,770 --> 00:10:34,400 So it might not be immediately clear. 208 00:10:34,400 --> 00:10:37,320 And if that is the case, then you might have a situation 209 00:10:37,320 --> 00:10:41,200 where people arrive from outside and give you this 210 00:10:41,200 --> 00:10:44,340 message, and say, you should really change your 211 00:10:44,340 --> 00:10:45,700 diet in this way. 212 00:10:45,700 --> 00:10:49,360 And you make, maybe, an effort to follow them for some time. 213 00:10:49,360 --> 00:10:52,540 Spend a little bit more money, or a little bit more effort 214 00:10:52,540 --> 00:10:55,740 into going into pasturizing your food. 215 00:10:55,740 --> 00:10:58,310 And then it happens, and you're not any stronger. 216 00:10:58,310 --> 00:11:00,990 And you're like, whatever did they tell me? 217 00:11:00,990 --> 00:11:03,420 It's like, this is no better. 218 00:11:03,420 --> 00:11:08,240 Because your expectations were set high enough to encourage 219 00:11:08,240 --> 00:11:09,760 you to do the switch. 220 00:11:09,760 --> 00:11:13,510 And the problem is there would be a tendency to slightly 221 00:11:13,510 --> 00:11:17,230 oversell how much better you're going to feel. 222 00:11:17,230 --> 00:11:19,490 Which then is going to translate into a 223 00:11:19,490 --> 00:11:21,240 disappointment. 224 00:11:21,240 --> 00:11:26,230 So one example of that is something that people have 225 00:11:26,230 --> 00:11:30,120 found in a deworming program in Kenya, which we're going to 226 00:11:30,120 --> 00:11:32,450 discuss in a moment. 227 00:11:32,450 --> 00:11:34,950 So it's a charitable deworming program. 228 00:11:34,950 --> 00:11:39,520 Deworming is, in some sense, a nutrition program, because the 229 00:11:39,520 --> 00:11:43,600 worms are competing with the kid for the food. 230 00:11:43,600 --> 00:11:48,500 So by removing the worms, you are increasing the amount of 231 00:11:48,500 --> 00:11:50,260 food that stays with the kid. 232 00:11:50,260 --> 00:11:53,230 I'm sorry, this is not a great conversation to have right 233 00:11:53,230 --> 00:11:53,880 after lunch. 234 00:11:53,880 --> 00:11:58,610 But that's kind of the biology of it, in two words. 235 00:11:58,610 --> 00:12:00,640 So when you give deworming-- 236 00:12:00,640 --> 00:12:02,330 and we are going to see that in a minute-- that 237 00:12:02,330 --> 00:12:05,752 does make the kid-- 238 00:12:05,752 --> 00:12:13,480 that reduces anemia, that reduces the 239 00:12:13,480 --> 00:12:15,370 incidence of being sick. 240 00:12:15,370 --> 00:12:20,140 That reduces, therefore, absence from school. 241 00:12:20,140 --> 00:12:27,050 So there was an NGO that was trying to promote deworming in 242 00:12:27,050 --> 00:12:33,120 some randomly-selected schools in the late '90s, early 2000s. 243 00:12:33,120 --> 00:12:35,650 And they went, and they explained all of this with a 244 00:12:35,650 --> 00:12:38,970 lot of energy, and said, your kid is going to feel much 245 00:12:38,970 --> 00:12:43,100 better, and is going to go to school more, and all of that. 246 00:12:43,100 --> 00:12:48,350 And parents had to sign a form to agree 247 00:12:48,350 --> 00:12:49,790 to get the kid dewormed. 248 00:12:49,790 --> 00:12:52,020 So it's not money. 249 00:12:52,020 --> 00:12:53,190 It's not a huge amount of effort. 250 00:12:53,190 --> 00:12:55,390 But it's still a little bit of effort. 251 00:12:55,390 --> 00:12:57,980 And also, you have to want it. 252 00:12:57,980 --> 00:12:59,950 And people were interested-- 253 00:12:59,950 --> 00:13:03,740 the researches were interested to know whether parents were 254 00:13:03,740 --> 00:13:07,760 more likely to sign the form if they knew more people 255 00:13:07,760 --> 00:13:11,150 around them who got a chance to get the deworming. 256 00:13:11,150 --> 00:13:15,775 So because it was a randomized experiment, which was done at 257 00:13:15,775 --> 00:13:17,230 the level of the school-- 258 00:13:17,230 --> 00:13:19,480 I'm going to show you a map in a moment-- 259 00:13:19,480 --> 00:13:23,130 some people got treated in some schools, and some people 260 00:13:23,130 --> 00:13:25,380 didn't get treated immediately. 261 00:13:25,380 --> 00:13:29,010 So people who are in a treated schools may have had friends 262 00:13:29,010 --> 00:13:31,390 who were in neighboring schools, which may have been 263 00:13:31,390 --> 00:13:33,280 treated a control. 264 00:13:33,280 --> 00:13:36,650 So what the researchers did is to look at whether you were 265 00:13:36,650 --> 00:13:39,470 more likely to take up the deworming once you got the 266 00:13:39,470 --> 00:13:42,560 option if you had more friends who got the 267 00:13:42,560 --> 00:13:44,740 option the year before. 268 00:13:44,740 --> 00:13:48,360 And their prior going into this, was that the more 269 00:13:48,360 --> 00:13:52,480 friends you have who got into the deworming, the more you 270 00:13:52,480 --> 00:13:54,810 are likely to do it yourself, because you 271 00:13:54,810 --> 00:13:56,960 will see the benefits. 272 00:13:56,960 --> 00:13:59,760 And what they found was exactly the opposite. 273 00:13:59,760 --> 00:14:03,170 Which is the more friends you had who had been a chance to 274 00:14:03,170 --> 00:14:06,360 get dewormed a year before, the less you are likely to 275 00:14:06,360 --> 00:14:09,590 take up the deworming once you got a chance. 276 00:14:09,590 --> 00:14:12,410 And what are the possible interpretations for that 277 00:14:12,410 --> 00:14:13,540 somewhat weird results? 278 00:14:13,540 --> 00:14:15,530 Yeah, Zach? 279 00:14:15,530 --> 00:14:16,940 AUDIENCE: One possible interpretation is that it 280 00:14:16,940 --> 00:14:19,105 depends on how you get the worms. 281 00:14:19,105 --> 00:14:21,932 The fact that your friends are being treated for you might be 282 00:14:21,932 --> 00:14:24,302 less likely to get it, like in the case of malaria. 283 00:14:24,302 --> 00:14:26,198 If everybody in the community's using the bednet, 284 00:14:26,198 --> 00:14:27,620 you probably don't have to. 285 00:14:27,620 --> 00:14:28,100 PROFESSOR: Exactly. 286 00:14:28,100 --> 00:14:30,900 So that's a first possible interpretation, which is worms 287 00:14:30,900 --> 00:14:33,250 are, in fact, highly contagious. 288 00:14:33,250 --> 00:14:37,330 So if most of your friends are treated, then they probably 289 00:14:37,330 --> 00:14:38,390 don't have worms anymore. 290 00:14:38,390 --> 00:14:42,010 You might feel, well, I don't need to go to the trouble of 291 00:14:42,010 --> 00:14:44,480 getting dewormed because they did, therefore there are fewer 292 00:14:44,480 --> 00:14:45,290 worms around. 293 00:14:45,290 --> 00:14:46,550 And there is some side effect. 294 00:14:46,550 --> 00:14:48,150 Why would you take the trouble? 295 00:14:48,150 --> 00:14:49,068 Yeah, Norm? 296 00:14:49,068 --> 00:14:52,510 AUDIENCE: Maybe people also, since people get dewormed, and 297 00:14:52,510 --> 00:14:55,996 then their problems decrease, people don't think it's as 298 00:14:55,996 --> 00:14:58,102 much of an issue, because it's not as prominent. 299 00:14:58,102 --> 00:15:01,504 So it's the externality just decreasing, they just don't 300 00:15:01,504 --> 00:15:03,450 realize that it's such a big threat anymore. 301 00:15:03,450 --> 00:15:04,180 PROFESSOR: Exactly. 302 00:15:04,180 --> 00:15:05,750 So that could be another thing. 303 00:15:05,750 --> 00:15:10,130 Which is, people learn that-- 304 00:15:10,130 --> 00:15:14,810 So people say, oh, these other kids got dewormed, but they 305 00:15:14,810 --> 00:15:17,912 are not much healthier than me. 306 00:15:17,912 --> 00:15:20,440 And the fact is, you don't realize that you are healthy 307 00:15:20,440 --> 00:15:23,060 because they are healthy, and they made you healthier. 308 00:15:23,060 --> 00:15:27,870 So you are now comparing the benefits of you as a control 309 00:15:27,870 --> 00:15:29,600 child-- you are not yet treated-- 310 00:15:29,600 --> 00:15:31,860 to the other kids who got treated. 311 00:15:31,860 --> 00:15:33,870 And the difference is not that large. 312 00:15:33,870 --> 00:15:37,000 It's not that large precisely because of the contagion 313 00:15:37,000 --> 00:15:38,640 effect that Zack mentioned. 314 00:15:38,640 --> 00:15:40,845 But so you're trying to learn the effect, and so it's not 315 00:15:40,845 --> 00:15:41,710 that large. 316 00:15:41,710 --> 00:15:43,910 And even if you don't understand that it's due to 317 00:15:43,910 --> 00:15:46,320 the externality, so you don't do this calculation, saying, 318 00:15:46,320 --> 00:15:47,470 it's not worthwhile. 319 00:15:47,470 --> 00:15:49,800 You just see it and think, what did they sell me? 320 00:15:49,800 --> 00:15:51,970 This thing doesn't really make any difference. 321 00:15:51,970 --> 00:15:53,360 And so you decide not to do it. 322 00:15:53,360 --> 00:15:53,854 Yeah. 323 00:15:53,854 --> 00:15:56,324 AUDIENCE: I was going to say that, even if you don't really 324 00:15:56,324 --> 00:15:59,946 have any change in your health status, maybe the change that 325 00:15:59,946 --> 00:16:02,086 the other people have is not so great as to 326 00:16:02,086 --> 00:16:03,734 convince you to get it. 327 00:16:03,734 --> 00:16:07,200 You see that the medication quote, unquote, doesn't work. 328 00:16:07,200 --> 00:16:08,040 PROFESSOR: Right. 329 00:16:08,040 --> 00:16:09,250 That also could be the case. 330 00:16:09,250 --> 00:16:11,540 Could be that, even without this mechanism-- 331 00:16:11,540 --> 00:16:14,610 which is a very nice one-- but even without this mechanism, 332 00:16:14,610 --> 00:16:16,590 you could see the other children and say, well, first 333 00:16:16,590 --> 00:16:19,620 thing, they got sick when they ate the deworming pill. 334 00:16:19,620 --> 00:16:21,110 So the side effect is immediate. 335 00:16:24,630 --> 00:16:25,820 It's getting worse and worse. 336 00:16:25,820 --> 00:16:31,010 But as the worm dies, this make you pretty unwell for an 337 00:16:31,010 --> 00:16:34,770 hour or two, as your body gets rid of them. 338 00:16:34,770 --> 00:16:36,310 And then you get better. 339 00:16:36,310 --> 00:16:38,950 But the side effect is salient and immediate, and the 340 00:16:38,950 --> 00:16:43,010 benefits are a little bit less apparent. 341 00:16:43,010 --> 00:16:46,530 And this, of course, is reinforced by the 342 00:16:46,530 --> 00:16:47,790 point that Norm made. 343 00:16:47,790 --> 00:16:50,120 Which is that the externalities make it 344 00:16:50,120 --> 00:16:53,030 difficult to compare treatment and control. 345 00:16:53,030 --> 00:16:56,180 So for all of these reasons-- 346 00:16:56,180 --> 00:17:01,390 so this is one example of why it's very difficult for people 347 00:17:01,390 --> 00:17:08,099 to learn about relatively subtle nutrition mechanisms. 348 00:17:08,099 --> 00:17:11,579 And so what is happening with deworming, that's maybe made a 349 00:17:11,579 --> 00:17:16,319 little bit harder but the externalities, which, A, gives 350 00:17:16,319 --> 00:17:16,849 [INAUDIBLE] 351 00:17:16,849 --> 00:17:19,869 like strategic reasons not to do it. 352 00:17:19,869 --> 00:17:21,790 So worms give Norms' difficulty of learning 353 00:17:21,790 --> 00:17:23,040 explanation. 354 00:17:25,650 --> 00:17:29,350 But that's could also be at play with iron pill, or 355 00:17:29,350 --> 00:17:32,220 supplementing your flour with iron. 356 00:17:32,220 --> 00:17:37,280 Where you're like, really not that much is. happening. 357 00:17:37,280 --> 00:17:41,630 So these are possible reasons why you wouldn't do what the 358 00:17:41,630 --> 00:17:45,360 good man, or well-meaning NGO tells you to do. 359 00:17:45,360 --> 00:17:47,150 You don't have the information. 360 00:17:47,150 --> 00:17:50,040 Learning is difficult, because the effects are subtle. 361 00:17:50,040 --> 00:17:52,170 This implies spending more money. 362 00:17:52,170 --> 00:17:55,450 Nd maybe those foods are not even available for you in a 363 00:17:55,450 --> 00:17:56,780 convenient way. 364 00:17:56,780 --> 00:17:59,826 What else could be going on, potentially? 365 00:17:59,826 --> 00:18:02,814 AUDIENCE: If the wages are set wages, then even if you eat 366 00:18:02,814 --> 00:18:04,474 more stronger, you're still going to get the 367 00:18:04,474 --> 00:18:05,304 same amount of money. 368 00:18:05,304 --> 00:18:08,160 So there's no point in being more productive. 369 00:18:08,160 --> 00:18:08,590 PROFESSOR: Right. 370 00:18:08,590 --> 00:18:11,240 So another possible explanation is you could 371 00:18:11,240 --> 00:18:13,500 realize that it's going to make you a bit more 372 00:18:13,500 --> 00:18:17,400 productive, but you might wonder, what's the use of me 373 00:18:17,400 --> 00:18:20,660 being more productive if, in fact, the wages are not piece 374 00:18:20,660 --> 00:18:22,620 wage but day wage? 375 00:18:22,620 --> 00:18:24,420 And you are a little bit more productive. 376 00:18:24,420 --> 00:18:27,810 But you need to go and convince your employer that 377 00:18:27,810 --> 00:18:30,080 now I'm a little bit more productive, so you need to pay 378 00:18:30,080 --> 00:18:32,080 me more on a daily basis. 379 00:18:32,080 --> 00:18:34,630 But your employer is not behind your back, checking 380 00:18:34,630 --> 00:18:36,660 what it is you're eating every day. 381 00:18:36,660 --> 00:18:39,960 And so your consumption is an upsell from the point of view 382 00:18:39,960 --> 00:18:41,390 of the employer. 383 00:18:41,390 --> 00:18:43,310 But there is a more moral hazard issue, where you could 384 00:18:43,310 --> 00:18:46,380 go and say, I'm telling you I've eaten so much. 385 00:18:46,380 --> 00:18:47,380 I'm very strong. 386 00:18:47,380 --> 00:18:49,780 You can monitor, you can see. 387 00:18:49,780 --> 00:18:52,240 Unless your employer can really be monitoring your 388 00:18:52,240 --> 00:18:56,640 output in a very close way, which might not always be 389 00:18:56,640 --> 00:18:59,670 possible, then they might say, whatever. 390 00:18:59,670 --> 00:19:03,510 I'm just assuming that you are the average person. 391 00:19:03,510 --> 00:19:12,070 And there is one study that shows that shows employers 392 00:19:12,070 --> 00:19:15,550 recognize that taller people are more productive. 393 00:19:15,550 --> 00:19:18,680 Taller people usually have been better fed, maybe, when 394 00:19:18,680 --> 00:19:19,930 they grew up. 395 00:19:19,930 --> 00:19:21,230 And they are stronger. 396 00:19:21,230 --> 00:19:23,380 Taller, maybe stronger, more muscles. 397 00:19:23,380 --> 00:19:25,950 People are more productive, they pay them more. 398 00:19:25,950 --> 00:19:29,800 But how much you've eaten and how well you've eaten 399 00:19:29,800 --> 00:19:32,730 previously does not affect wages. 400 00:19:32,730 --> 00:19:34,850 And that is because that isn't observed from the point of 401 00:19:34,850 --> 00:19:35,760 view of the employer. 402 00:19:35,760 --> 00:19:41,320 And if they can't see the output either, it's 403 00:19:41,320 --> 00:19:42,630 he said, she said. 404 00:19:42,630 --> 00:19:45,490 How do I know you're actually more productive? 405 00:19:45,490 --> 00:19:47,870 So of course, the solution to that would be for the employer 406 00:19:47,870 --> 00:19:50,490 to feed people iron supplement on the job. 407 00:19:50,490 --> 00:19:53,490 And why they're not doing that, I don't know. 408 00:19:53,490 --> 00:19:57,190 But that would be an interesting thing to consider. 409 00:19:57,190 --> 00:19:58,250 Because then they could know. 410 00:19:58,250 --> 00:19:59,330 They could say, yeah. 411 00:19:59,330 --> 00:20:01,260 I can pay you a bit more, as long as you are eating your 412 00:20:01,260 --> 00:20:02,510 iron supplement. 413 00:20:04,860 --> 00:20:09,930 So let's go to all of this in a little more systematic way. 414 00:20:09,930 --> 00:20:13,910 So the first thing we need to check is, all of this learning 415 00:20:13,910 --> 00:20:14,540 is going to be-- 416 00:20:14,540 --> 00:20:19,310 I think people are very naturally associating more 417 00:20:19,310 --> 00:20:21,750 calories with more strength. 418 00:20:21,750 --> 00:20:24,740 Even we have this in mind-- to a point, 419 00:20:24,740 --> 00:20:27,730 until we eat too much. 420 00:20:27,730 --> 00:20:31,090 But this is probably harder to learn about-- micronutrient 421 00:20:31,090 --> 00:20:32,620 deficiency. 422 00:20:32,620 --> 00:20:35,550 Because that's not something that is as obvious, and you 423 00:20:35,550 --> 00:20:37,220 don't necessarily know which foods have what 424 00:20:37,220 --> 00:20:38,880 nutrients, et cetera. 425 00:20:38,880 --> 00:20:41,620 And so the first thing we need to establish is that 426 00:20:41,620 --> 00:20:44,520 micronutrient deficiency actually matters. 427 00:20:44,520 --> 00:20:51,160 And in particular, that the poor and even the not-so-poor 428 00:20:51,160 --> 00:20:59,680 could become more productive if they got more micronutrient 429 00:20:59,680 --> 00:21:02,330 supplementation in their diet. 430 00:21:02,330 --> 00:21:08,600 For that, of course, we could compound the wages of people 431 00:21:08,600 --> 00:21:11,820 who have more hemoglobin in their blood and the wages of 432 00:21:11,820 --> 00:21:14,310 people who have less hemoglobin in their blood. 433 00:21:14,310 --> 00:21:16,390 If we do that, what do you think we will find? 434 00:21:20,950 --> 00:21:22,870 Most likely? 435 00:21:22,870 --> 00:21:25,870 We look at the data set, and we look at the wages of anemic 436 00:21:25,870 --> 00:21:29,420 people versus the wages of non-anemic people? 437 00:21:29,420 --> 00:21:30,626 Richard? 438 00:21:30,626 --> 00:21:32,944 AUDIENCE: Of course, the non-anemic people have more 439 00:21:32,944 --> 00:21:35,484 strength to go to work, so their wages are higher if they 440 00:21:35,484 --> 00:21:37,110 are paid by the [INAUDIBLE]. 441 00:21:37,110 --> 00:21:38,940 PROFESSOR: So the non-anemic people, when we do this 442 00:21:38,940 --> 00:21:40,960 comparison, will make more money. 443 00:21:40,960 --> 00:21:43,540 That's sure poverty in every data set, we're 444 00:21:43,540 --> 00:21:44,740 going to find that. 445 00:21:44,740 --> 00:21:48,300 But once we find that, can we for sure say it's the effect 446 00:21:48,300 --> 00:21:49,550 of being anemic? 447 00:21:52,678 --> 00:21:53,666 AUDIENCE: Not necessarily. 448 00:21:53,666 --> 00:21:56,186 It could be environmental factors. 449 00:21:56,186 --> 00:21:58,601 You could be anemic because you don't make [INAUDIBLE] 450 00:21:58,601 --> 00:22:02,465 enough to have a proper diet, or you could not have wages 451 00:22:02,465 --> 00:22:03,930 because you're anemic. 452 00:22:03,930 --> 00:22:04,320 PROFESSOR: Right. 453 00:22:04,320 --> 00:22:05,960 So there's two things. 454 00:22:05,960 --> 00:22:08,390 So first, they could be a reverse causality at play. 455 00:22:08,390 --> 00:22:10,630 Which is, you could be anemic because you don't own enough 456 00:22:10,630 --> 00:22:12,050 to buy spinach. 457 00:22:12,050 --> 00:22:12,810 That's one. 458 00:22:12,810 --> 00:22:14,570 And what else could be at play? 459 00:22:17,720 --> 00:22:20,560 Even if we manage to shut down this mechanism, or assume that 460 00:22:20,560 --> 00:22:22,320 specific mechanism is not there? 461 00:22:27,130 --> 00:22:29,935 What could be other things that would explain this 462 00:22:29,935 --> 00:22:31,700 correlation between anemia and [INAUDIBLE]? 463 00:22:41,200 --> 00:22:42,450 AUDIENCE: It might be some other third 464 00:22:42,450 --> 00:22:44,200 factor that causes both. 465 00:22:44,200 --> 00:22:46,950 For instance, your social status, perhaps, means you can 466 00:22:46,950 --> 00:22:48,700 only get a certain kind of job. 467 00:22:48,700 --> 00:22:53,450 And it also means that it's harder for you to get good 468 00:22:53,450 --> 00:22:55,640 wages and then get better diet. 469 00:22:55,640 --> 00:22:56,090 PROFESSOR: Right. 470 00:22:56,090 --> 00:22:59,460 There could be something that explains both. 471 00:22:59,460 --> 00:23:03,610 For example, your social status, or for example, how 472 00:23:03,610 --> 00:23:08,270 well-educated you are, or the types of opportunities you 473 00:23:08,270 --> 00:23:09,080 have access to. 474 00:23:09,080 --> 00:23:12,140 Or anything like that would both effect your 475 00:23:12,140 --> 00:23:13,560 anemia and your wage. 476 00:23:13,560 --> 00:23:15,750 So we don't know. 477 00:23:15,750 --> 00:23:18,880 So that's something which is actually relatively easy to 478 00:23:18,880 --> 00:23:24,960 organize as a randomized experiment, because you can 479 00:23:24,960 --> 00:23:28,240 pretty much cure anemia, at least temporarily, by giving 480 00:23:28,240 --> 00:23:29,490 people iron supplements. 481 00:23:32,080 --> 00:23:35,290 So that's almost like a medical study you can give 482 00:23:35,290 --> 00:23:35,720 some people. 483 00:23:35,720 --> 00:23:37,980 So this was done in Indonesia. 484 00:23:37,980 --> 00:23:43,720 The WISE stands for Work and Iron Status Evaluation. 485 00:23:43,720 --> 00:23:43,830 They 486 00:23:43,830 --> 00:23:47,180 They worked with several thousand households. 487 00:23:47,180 --> 00:23:51,090 And they provided them with either an iron supplement or a 488 00:23:51,090 --> 00:23:54,790 placebo in a randomly-selected way. 489 00:23:54,790 --> 00:23:56,660 So they randomized the household. 490 00:23:56,660 --> 00:23:58,910 And once they pick a household's treatment, they 491 00:23:58,910 --> 00:24:02,200 give everyone in the household the iron supplement. 492 00:24:02,200 --> 00:24:06,260 It takes a few months for people to absorb the iron and 493 00:24:06,260 --> 00:24:08,540 to become iron-replete. 494 00:24:08,540 --> 00:24:12,000 Once you're not anemic, you have enough iron in your body, 495 00:24:12,000 --> 00:24:13,750 you get rid of the rest. 496 00:24:13,750 --> 00:24:16,430 So anemia is something which is, either you are anemic or 497 00:24:16,430 --> 00:24:17,580 you're not. 498 00:24:17,580 --> 00:24:20,790 And once you're not-- that is, once your hemoglobin is above 499 00:24:20,790 --> 00:24:25,940 13 for men, and for women it's between 11 and 12. 500 00:24:25,940 --> 00:24:29,470 That's gram per deciliter. 501 00:24:29,470 --> 00:24:31,780 You just stop absorbing it. 502 00:24:31,780 --> 00:24:35,750 So what they found when they gave this iron supplement is 503 00:24:35,750 --> 00:24:40,580 that there is no effect of comparing the people who got 504 00:24:40,580 --> 00:24:43,910 the placebo and people who got the pill if they were not 505 00:24:43,910 --> 00:24:44,680 anemic before. 506 00:24:44,680 --> 00:24:46,280 There is no impact on them. 507 00:24:46,280 --> 00:24:48,630 That's exactly what you would expect, because once you have 508 00:24:48,630 --> 00:24:49,440 enough, you have enough. 509 00:24:49,440 --> 00:24:51,270 There is nothing more we can tell you. 510 00:24:51,270 --> 00:24:54,440 On the other hand, the more anemic you were before-- that 511 00:24:54,440 --> 00:24:57,180 is, the further you were from 12 grams per deciliter of 512 00:24:57,180 --> 00:25:00,140 hemoglobin in your blood-- 513 00:25:00,140 --> 00:25:04,970 the larger the effect, in terms of the increase in 514 00:25:04,970 --> 00:25:06,330 hemoglobin in your blood. 515 00:25:06,330 --> 00:25:08,710 That is, what they found is that the people who got the 516 00:25:08,710 --> 00:25:13,110 supplement almost all got to 12, or close to 12. 517 00:25:13,110 --> 00:25:15,700 So the further away you were from 12, 518 00:25:15,700 --> 00:25:17,580 the bigger the effect. 519 00:25:17,580 --> 00:25:20,660 And so, once they do that, they can separately at people 520 00:25:20,660 --> 00:25:23,350 who were anemic at baseline and people who weren't. 521 00:25:23,350 --> 00:25:28,010 And they found that if you focus on people who were 522 00:25:28,010 --> 00:25:35,120 anemic at baseline, and people who were self-employed, those 523 00:25:35,120 --> 00:25:39,660 people made substantially more money after they received the 524 00:25:39,660 --> 00:25:40,610 iron supplement. 525 00:25:40,610 --> 00:25:44,490 So they looked at the wages eight months after the iron 526 00:25:44,490 --> 00:25:45,910 supplement starts. 527 00:25:45,910 --> 00:25:48,910 And then there is another end line a few months later. 528 00:25:48,910 --> 00:25:51,320 And they find these people to make more money. 529 00:25:51,320 --> 00:25:54,280 So about $40 more per year. 530 00:25:54,280 --> 00:25:58,140 Which is not nothing. 531 00:25:58,140 --> 00:25:59,750 This is not an enormous amount. 532 00:25:59,750 --> 00:26:03,975 This is not a doubling of the wage or anything. 533 00:26:03,975 --> 00:26:08,220 The yearly wages of these people may have been around 534 00:26:08,220 --> 00:26:09,920 $500 or something like that. 535 00:26:09,920 --> 00:26:13,290 So it's maybe a little less than 10% increase. 536 00:26:13,290 --> 00:26:16,470 But this is very cheap. 537 00:26:16,470 --> 00:26:18,470 Because if someone wanted to-- 538 00:26:18,470 --> 00:26:21,400 well, actually the experiment itself was very expensive. 539 00:26:21,400 --> 00:26:24,230 Because they had to go behind people's backs and make sure 540 00:26:24,230 --> 00:26:26,110 that actually eat the pill. 541 00:26:26,110 --> 00:26:28,670 And they had so many nurses, and they were really 542 00:26:28,670 --> 00:26:31,220 controlling that they were following the protocol. 543 00:26:31,220 --> 00:26:33,870 So for the experiment itself, costs much more 544 00:26:33,870 --> 00:26:36,120 than $40 per person. 545 00:26:36,120 --> 00:26:41,290 But what they argue in their paper is that that's not 546 00:26:41,290 --> 00:26:44,660 really interesting, because if someone wanted to do it, they 547 00:26:44,660 --> 00:26:46,690 could just buy 45 fish sauce. 548 00:26:46,690 --> 00:26:48,817 And that would cost them only $6. 549 00:26:48,817 --> 00:26:49,314 Yep. 550 00:26:49,314 --> 00:26:52,129 AUDIENCE: In the experiment, do they control for the fact 551 00:26:52,129 --> 00:26:55,775 that people usually earn higher wages as time passes? 552 00:26:55,775 --> 00:26:58,757 So next year, my wage is probably going to be higher 553 00:26:58,757 --> 00:27:00,248 than this year, because I have more experience. 554 00:27:00,248 --> 00:27:02,236 It means I can get a better wage. 555 00:27:02,236 --> 00:27:04,230 I'm better at catching fish. 556 00:27:04,230 --> 00:27:04,590 PROFESSOR: Right. 557 00:27:04,590 --> 00:27:05,190 That's an excellent point. 558 00:27:05,190 --> 00:27:10,250 You're saying you would want to control for the fact that 559 00:27:10,250 --> 00:27:12,180 as time passes, you earn more money. 560 00:27:12,180 --> 00:27:14,910 So how would they be able to do that in the context of this 561 00:27:14,910 --> 00:27:15,640 experiment? 562 00:27:15,640 --> 00:27:20,122 AUDIENCE: Maybe there's a historical [INAUDIBLE]. 563 00:27:20,122 --> 00:27:22,861 I'd like to figure out how much people would earn over 564 00:27:22,861 --> 00:27:25,102 their lifetime in that region, and then control for that 565 00:27:25,102 --> 00:27:26,596 percentage. 566 00:27:26,596 --> 00:27:30,082 And they can account-- maybe in the $40 increase, there is 567 00:27:30,082 --> 00:27:35,560 $22 into that that is perhaps due to the [INAUDIBLE] 568 00:27:35,560 --> 00:27:37,580 average increase in wages. 569 00:27:37,580 --> 00:27:40,790 PROFESSOR: And so you're saying what they could do to 570 00:27:40,790 --> 00:27:42,880 control for an historical trend is to try to find out 571 00:27:42,880 --> 00:27:45,185 what the historical trend would have been. 572 00:27:45,185 --> 00:27:49,490 And in particular, what is in their data that tells them 573 00:27:49,490 --> 00:27:52,160 what the historical trend would have been, 574 00:27:52,160 --> 00:27:53,500 directly free of charge. 575 00:27:53,500 --> 00:27:55,270 Not free of charge, because that was in the design. 576 00:27:55,270 --> 00:27:56,520 But once you have the experiment. 577 00:27:59,200 --> 00:27:59,410 Yeah. 578 00:27:59,410 --> 00:28:00,330 AUDIENCE: The control group. 579 00:28:00,330 --> 00:28:00,870 PROFESSOR: The control group. 580 00:28:00,870 --> 00:28:02,040 There is a placebo group. 581 00:28:02,040 --> 00:28:04,850 So half the sample gets nothing. 582 00:28:04,850 --> 00:28:07,890 So what they actually do in the experiment is they compare 583 00:28:07,890 --> 00:28:12,635 the wage growth of people who got the program to people who 584 00:28:12,635 --> 00:28:13,700 got the placebo. 585 00:28:13,700 --> 00:28:15,830 In fact, here they compare the wage growth of the 586 00:28:15,830 --> 00:28:20,320 self-employed people who were anemic at baseline in the 587 00:28:20,320 --> 00:28:22,660 treatment group and in the control group. 588 00:28:22,660 --> 00:28:26,160 And you are exactly right that those wages 589 00:28:26,160 --> 00:28:28,610 increase in both cases. 590 00:28:28,610 --> 00:28:31,220 But they increased faster in the treatment group. 591 00:28:31,220 --> 00:28:34,270 And the $40 is the difference in the growth. 592 00:28:34,270 --> 00:28:35,770 So it's already accounting for that. 593 00:28:38,650 --> 00:28:42,490 So what I say is that, well, if someone wanted to do it on 594 00:28:42,490 --> 00:28:45,250 the own, that wouldn't cost them so much money. 595 00:28:45,250 --> 00:28:52,420 That would just cost them $6 per year for a gain of $40. 596 00:28:52,420 --> 00:28:56,120 So this is a case where you would think it's something 597 00:28:56,120 --> 00:28:58,630 that starts looking like an S-shape. 598 00:28:58,630 --> 00:29:03,710 Which is, if you become rich enough for spending an extra 599 00:29:03,710 --> 00:29:08,492 $6, you actually get a return which is much higher than $6. 600 00:29:08,492 --> 00:29:13,030 So you may have this increasing return that is 601 00:29:13,030 --> 00:29:16,465 necessary for the poverty trap to emerge, where the slightly 602 00:29:16,465 --> 00:29:19,280 richer people get the fortified fish sauce instead 603 00:29:19,280 --> 00:29:22,590 of the regular fish sauce that costs them $6, and 604 00:29:22,590 --> 00:29:24,340 they make $40 extra. 605 00:29:27,100 --> 00:29:28,480 So you could say, well, there is something. 606 00:29:28,480 --> 00:29:30,200 Except that, of course, you have to ask. 607 00:29:30,200 --> 00:29:34,400 $6 is not all that much, so what is preventing these poor 608 00:29:34,400 --> 00:29:38,470 people to pay $6? 609 00:29:38,470 --> 00:29:42,600 So that is the first place where, if we compare this, 40 610 00:29:42,600 --> 00:29:45,555 to 6 is the first place where we can see a poverty trap. 611 00:29:45,555 --> 00:29:48,140 Except we'll have to explain why it's there. 612 00:29:48,140 --> 00:29:51,250 We'll have to explain why it seems that the poor people are 613 00:29:51,250 --> 00:29:53,485 less likely to spend the $6 on fortified fish 614 00:29:53,485 --> 00:29:54,735 sauce in their reach. 615 00:29:57,490 --> 00:29:58,850 That's for adults. 616 00:29:58,850 --> 00:30:01,800 So already, we saw that for calories, we don't see such a 617 00:30:01,800 --> 00:30:03,810 big return to calorie consumption. 618 00:30:03,810 --> 00:30:05,870 By for iron, we see it. 619 00:30:05,870 --> 00:30:09,480 Now, another place where we do see, potentially, very large 620 00:30:09,480 --> 00:30:13,860 returns of investing into food is when you're trying to 621 00:30:13,860 --> 00:30:17,800 invest in the nutrition of your children. 622 00:30:17,800 --> 00:30:25,940 So why is it that, even though if we're 623 00:30:25,940 --> 00:30:27,520 talking about calories-- 624 00:30:27,520 --> 00:30:31,360 even more micronutrients, but any kind of 625 00:30:31,360 --> 00:30:34,280 investment in your children-- 626 00:30:34,280 --> 00:30:37,290 may have a larger impact than the same 627 00:30:37,290 --> 00:30:40,610 investment for an adult? 628 00:30:40,610 --> 00:30:42,590 AUDIENCE: Because children are still growing and developing. 629 00:30:42,590 --> 00:30:45,560 Their brains are still growing, and their bones. 630 00:30:45,560 --> 00:30:49,355 Basically, the frame for who their going to be is in 631 00:30:49,355 --> 00:30:51,005 development at this point in their life. 632 00:30:51,005 --> 00:30:54,322 So it's important that they can reach their potential by 633 00:30:54,322 --> 00:30:57,250 giving them the nutrients that they need now. 634 00:30:57,250 --> 00:30:58,250 PROFESSOR: Right. 635 00:30:58,250 --> 00:31:00,180 AUDIENCE: [INAUDIBLE]. 636 00:31:00,180 --> 00:31:00,610 PROFESSOR: Exactly. 637 00:31:00,610 --> 00:31:06,250 So the first reason, pure health reason, is that when 638 00:31:06,250 --> 00:31:08,910 you're investing into a child's nutrition, be it 639 00:31:08,910 --> 00:31:11,860 calorie or micronutrient, you don't only make the child more 640 00:31:11,860 --> 00:31:15,340 productive tomorrow, you are changing the adult that this 641 00:31:15,340 --> 00:31:16,780 child is going to be. 642 00:31:16,780 --> 00:31:19,740 You are making this person reach their genetic potential 643 00:31:19,740 --> 00:31:22,270 in terms of height, for example, that they might not 644 00:31:22,270 --> 00:31:23,950 otherwise be getting. 645 00:31:23,950 --> 00:31:28,210 You are helping this person reach that 646 00:31:28,210 --> 00:31:29,890 potential in their brain. 647 00:31:29,890 --> 00:31:32,130 You're helping this person develop the muscles that they 648 00:31:32,130 --> 00:31:33,270 would have gotten. 649 00:31:33,270 --> 00:31:37,320 And some of these, you might not be able to recover later. 650 00:31:37,320 --> 00:31:41,850 In particular, some of the nutritional deficiency that 651 00:31:41,850 --> 00:31:45,280 you get as very small children, in between weaning 652 00:31:45,280 --> 00:31:51,660 at about six months and two years, would be very easy to 653 00:31:51,660 --> 00:31:54,730 catch up once the child's actually gone. 654 00:31:54,730 --> 00:31:57,224 Even once a child is more than two. 655 00:31:57,224 --> 00:31:58,020 Yeah. 656 00:31:58,020 --> 00:31:59,958 AUDIENCE: There's no access to things like 657 00:31:59,958 --> 00:32:01,446 education at this point. 658 00:32:01,446 --> 00:32:03,926 So if they're better nourished now, then they 659 00:32:03,926 --> 00:32:04,918 can focus on that. 660 00:32:04,918 --> 00:32:07,563 Versus an adult probably wouldn't be thinking about 661 00:32:07,563 --> 00:32:09,900 going back to school at that point. 662 00:32:09,900 --> 00:32:10,155 PROFESSOR: Exactly. 663 00:32:10,155 --> 00:32:13,340 So the second reason is that, even if we forget this 664 00:32:13,340 --> 00:32:17,760 biological phenomenon, the job of a child is typically to be 665 00:32:17,760 --> 00:32:21,270 in school, or to learn things around them. 666 00:32:21,270 --> 00:32:22,320 Not necessarily in school. 667 00:32:22,320 --> 00:32:25,835 Some can be outside of school. 668 00:32:25,835 --> 00:32:29,220 They are still getting all the information in the world. 669 00:32:29,220 --> 00:32:31,040 That's what children do. 670 00:32:31,040 --> 00:32:36,060 And if you do this job better, then you are building your 671 00:32:36,060 --> 00:32:37,560 human capitol. 672 00:32:37,560 --> 00:32:41,650 Really think of it as like, the capitol of each of us is 673 00:32:41,650 --> 00:32:44,700 our health, which is affected by how much we eat directly. 674 00:32:44,700 --> 00:32:47,540 But also what we know, our experience, our 675 00:32:47,540 --> 00:32:49,340 education, et cetera. 676 00:32:49,340 --> 00:32:53,240 And if we do this job better as children, we'll have a 677 00:32:53,240 --> 00:32:56,550 better stock of education for the rest of our lives. 678 00:32:56,550 --> 00:32:58,760 Education and knowledge generally. 679 00:32:58,760 --> 00:33:03,000 And we are be going to get the return from that every year. 680 00:33:03,000 --> 00:33:07,035 So when we do our job better as an adult, we earn a higher 681 00:33:07,035 --> 00:33:08,330 wage and that's it. 682 00:33:08,330 --> 00:33:12,900 When we do our job better at your age, or even earlier, 683 00:33:12,900 --> 00:33:14,700 when you were a child, when you were a small child trying 684 00:33:14,700 --> 00:33:18,000 to learn things, since your job is to develop, that means 685 00:33:18,000 --> 00:33:19,524 you're better developed. 686 00:33:19,524 --> 00:33:21,612 AUDIENCE: Is it more important to have good nutrition when 687 00:33:21,612 --> 00:33:25,340 the mom's pregnant, or after the child's born? 688 00:33:25,340 --> 00:33:26,040 PROFESSOR: Both are important. 689 00:33:26,040 --> 00:33:29,920 We're going to get to the mom in a minute. 690 00:33:29,920 --> 00:33:33,720 But both children are important, and in utero is 691 00:33:33,720 --> 00:33:34,680 very important. 692 00:33:34,680 --> 00:33:36,570 Both of them are important. 693 00:33:36,570 --> 00:33:40,340 So for these reasons, if you take a child and you say, I'm 694 00:33:40,340 --> 00:33:43,550 going to feed this child better, if only between the 695 00:33:43,550 --> 00:33:45,930 time of six months to two years-- 696 00:33:45,930 --> 00:33:49,470 or let's say, even if you were going from six months to ten 697 00:33:49,470 --> 00:33:53,000 years, when they are in full development of their body and 698 00:33:53,000 --> 00:33:53,940 their mind. 699 00:33:53,940 --> 00:33:57,480 I'm going to then, on return, potentially, 700 00:33:57,480 --> 00:33:58,820 for his entire life. 701 00:33:58,820 --> 00:34:02,390 That means the size in difference in investment in 702 00:34:02,390 --> 00:34:05,130 how much you're going to get in the future compared to the 703 00:34:05,130 --> 00:34:08,139 investment you are making is much, much larger. 704 00:34:08,139 --> 00:34:11,489 And that can, again, give you the potential for an S-shape. 705 00:34:11,489 --> 00:34:15,110 Where a poorer person is going to invest a little less. 706 00:34:15,110 --> 00:34:17,799 And this difference at this points can be-- 707 00:34:17,799 --> 00:34:21,739 this difference in slightly smaller investment at critical 708 00:34:21,739 --> 00:34:26,889 range could translate into much, much smaller lifetime 709 00:34:26,889 --> 00:34:29,130 earning for a child. 710 00:34:29,130 --> 00:34:33,330 So let's see some examples of that. 711 00:34:33,330 --> 00:34:36,489 So the first one is the deworming example that I was 712 00:34:36,489 --> 00:34:38,110 talking about. 713 00:34:38,110 --> 00:34:41,590 And this was done, also, in a randomized experiment. 714 00:34:41,590 --> 00:34:43,340 That's the one I was talking to you about, where they 715 00:34:43,340 --> 00:34:51,600 realized that the more people you knew who took the 716 00:34:51,600 --> 00:34:54,100 deworming, the less likely you were to take it. 717 00:34:54,100 --> 00:34:55,940 Well, it turned out that was actually a mistake. 718 00:34:55,940 --> 00:35:00,570 Because being dewormed is extremely helpful. 719 00:35:00,570 --> 00:35:05,220 So what I did is, this is the region where they worked, 720 00:35:05,220 --> 00:35:08,600 where you had a bunch of schools. 721 00:35:08,600 --> 00:35:10,350 This is a map. 722 00:35:10,350 --> 00:35:16,500 You can see that the region is close to Lake Victoria. 723 00:35:16,500 --> 00:35:21,410 Worms, particularly schistosomasis, is something 724 00:35:21,410 --> 00:35:25,080 that you're much more likely to get if you are walking in 725 00:35:25,080 --> 00:35:27,710 the fresh water. 726 00:35:27,710 --> 00:35:29,170 Particularly when it's not that clean, but 727 00:35:29,170 --> 00:35:30,660 when it's not salty. 728 00:35:30,660 --> 00:35:35,140 So ones basically climb from the sole of your feet inside. 729 00:35:35,140 --> 00:35:38,560 So when these kids go fishing in the lake, or just go hang 730 00:35:38,560 --> 00:35:41,640 out in the lake, much more likely to get worms. 731 00:35:41,640 --> 00:35:44,350 So this region is infected by worms. 732 00:35:44,350 --> 00:35:47,810 About a quarter of the worm children suffer from worms. 733 00:35:47,810 --> 00:35:50,950 One thing with worms is that they've never killed anybody. 734 00:35:50,950 --> 00:35:52,720 At least, not these worms. 735 00:35:52,720 --> 00:35:55,480 There are some worms that gives you very 736 00:35:55,480 --> 00:35:58,250 spectacular, big legs. 737 00:35:58,250 --> 00:36:00,410 And those worms are a little bit more fashionable. 738 00:36:00,410 --> 00:36:03,990 But these little hookworm, schistosomasis, 739 00:36:03,990 --> 00:36:06,550 doesn't kill people. 740 00:36:06,550 --> 00:36:08,910 You can't really see that someone has them. 741 00:36:08,910 --> 00:36:10,990 So as a reason, it's not a disease that anybody's 742 00:36:10,990 --> 00:36:13,960 particularly excited about. 743 00:36:13,960 --> 00:36:17,536 I want to make you excited about worms for about, like, 744 00:36:17,536 --> 00:36:19,555 at least 15 minutes. 745 00:36:19,555 --> 00:36:22,140 You can come back and say, well, these worms, there is 746 00:36:22,140 --> 00:36:23,710 something with them. 747 00:36:23,710 --> 00:36:30,120 So the researcher went to this area, and they separated to 748 00:36:30,120 --> 00:36:32,840 schools into three groups randomly. 749 00:36:32,840 --> 00:36:36,400 Why did they pick the school? 750 00:36:36,400 --> 00:36:38,810 Why did they decide to randomize at the school level 751 00:36:38,810 --> 00:36:41,280 instead of doing it within school? 752 00:36:41,280 --> 00:36:43,960 For example, if you remember the bednet experiment, the 753 00:36:43,960 --> 00:36:46,540 bednet experiment was done at the individual level. 754 00:36:46,540 --> 00:36:49,790 Here, they treated all the children in the school. 755 00:36:49,790 --> 00:36:52,260 All the children was left as control. 756 00:36:52,260 --> 00:36:56,190 Why did they decide to do it at the school level? 757 00:36:56,190 --> 00:36:57,020 Yup. 758 00:36:57,020 --> 00:36:59,440 AUDIENCE: So kids may affect one another. 759 00:36:59,440 --> 00:37:03,150 So if one child in a classroom is dewormed and the other is 760 00:37:03,150 --> 00:37:04,764 not, they may be learning better. 761 00:37:04,764 --> 00:37:06,538 And because they're learning better, the other child may 762 00:37:06,538 --> 00:37:07,668 also be increasing their understanding. 763 00:37:07,668 --> 00:37:10,572 If you do it at a school level, they can cancel out 764 00:37:10,572 --> 00:37:11,056 that effect. 765 00:37:11,056 --> 00:37:13,330 So they can compare schools where all children are and 766 00:37:13,330 --> 00:37:14,580 schools where all children aren't. 767 00:37:14,580 --> 00:37:14,950 PROFESSOR: Right. 768 00:37:14,950 --> 00:37:17,010 So kids' education could affect one another. 769 00:37:17,010 --> 00:37:17,610 What else? 770 00:37:17,610 --> 00:37:20,613 In what way could they also affect one another? 771 00:37:20,613 --> 00:37:23,103 AUDIENCE: Isn't there the externality, because they're 772 00:37:23,103 --> 00:37:24,850 very contagious, you said? 773 00:37:24,850 --> 00:37:25,150 PROFESSOR: Right. 774 00:37:25,150 --> 00:37:29,930 There is the direct deworming externality that Zach and Noah 775 00:37:29,930 --> 00:37:30,870 mentioned earlier. 776 00:37:30,870 --> 00:37:34,260 Which is actually, worms are hyper-contagious. 777 00:37:34,260 --> 00:37:37,990 So if you compare, when they have done randomized 778 00:37:37,990 --> 00:37:40,450 experiments before within schools, they were very 779 00:37:40,450 --> 00:37:42,420 surprised, because they're saying, we are deworming these 780 00:37:42,420 --> 00:37:45,500 children, and we see no effect on anything. 781 00:37:45,500 --> 00:37:49,650 And the thing is, the control kids were re-infecting the 782 00:37:49,650 --> 00:37:51,900 treated kids, and the treated kids were also making the 783 00:37:51,900 --> 00:37:53,640 control kids less sick. 784 00:37:53,640 --> 00:37:56,140 So the effect was zero. 785 00:37:56,140 --> 00:37:58,640 So here, they decided, let's go and randomize the at the 786 00:37:58,640 --> 00:37:59,980 school level. 787 00:37:59,980 --> 00:38:04,890 And the first thing they did is that they 788 00:38:04,890 --> 00:38:08,370 went into the schools. 789 00:38:08,370 --> 00:38:10,480 So they did the school in three groups. 790 00:38:10,480 --> 00:38:14,680 They dewormed Group 1 in '98-2003, and then dewormed 791 00:38:14,680 --> 00:38:18,220 the Group 2 in 1999-2003, and dewormed the 792 00:38:18,220 --> 00:38:21,560 group three in 2001-2003. 793 00:38:21,560 --> 00:38:32,880 So the Group 3 three children got, on average, less two 794 00:38:32,880 --> 00:38:37,080 fewer years of deworming compared to the Group 1 and 2. 795 00:38:37,080 --> 00:38:40,190 There was a first study they did, which was they collected 796 00:38:40,190 --> 00:38:42,790 data in 2000. 797 00:38:42,790 --> 00:38:45,590 And in 2000, they compared children in Group 1 and 2 to 798 00:38:45,590 --> 00:38:46,950 children in Group 3. 799 00:38:46,950 --> 00:38:49,630 So children in Group 1 and 2 had been treated either one or 800 00:38:49,630 --> 00:38:51,930 two years, and children in Group 3 had not 801 00:38:51,930 --> 00:38:53,390 being treated yet. 802 00:38:53,390 --> 00:38:56,060 And what they found at this time was children, of course, 803 00:38:56,060 --> 00:38:58,390 were less likely to have worms if they had been dewormed. 804 00:38:58,390 --> 00:39:01,670 Otherwise, it's not much study to talk about. 805 00:39:01,670 --> 00:39:05,225 Number one is children who had been dewormed [INAUDIBLE], 806 00:39:05,225 --> 00:39:07,500 they are less likely to be anemic. 807 00:39:07,500 --> 00:39:10,630 And importantly, they are less likely to miss school. 808 00:39:10,630 --> 00:39:15,220 So they find that there was an increase of about 15%. 809 00:39:15,220 --> 00:39:20,790 So 1/6 of a year in participation in school. 810 00:39:20,790 --> 00:39:24,900 So what this study that we are doing now does is that it's 811 00:39:24,900 --> 00:39:28,280 tracking the children who were in primary school at this time 812 00:39:28,280 --> 00:39:30,400 later when they go up. 813 00:39:30,400 --> 00:39:35,490 So the date we're going to look at is in 2007-2009. 814 00:39:35,490 --> 00:39:43,940 So a kid who was 10 in 1998 is now 20, and is therefore 815 00:39:43,940 --> 00:39:46,350 usually doing something, working. 816 00:39:46,350 --> 00:39:48,890 And therefore, they can start looking at whether these 817 00:39:48,890 --> 00:39:50,420 people are now earning more money. 818 00:39:54,940 --> 00:39:58,650 So it's a big project, because these children have gone all 819 00:39:58,650 --> 00:40:00,270 over the place. 820 00:40:00,270 --> 00:40:04,570 So they have had some difficulty finding them. 821 00:40:04,570 --> 00:40:08,210 One of them was in London, and they went and interviewed a 822 00:40:08,210 --> 00:40:11,600 person in London. 823 00:40:11,600 --> 00:40:13,620 Many of them had moved to Nairobi or had moved to 824 00:40:13,620 --> 00:40:15,940 Mombasa or had moved to Uganda. 825 00:40:15,940 --> 00:40:18,510 So what they did is they did a first wave of it where they 826 00:40:18,510 --> 00:40:20,430 tried to track everyone. 827 00:40:20,430 --> 00:40:22,850 And they found about 60% of the people. 828 00:40:22,850 --> 00:40:27,740 And that's not enough, because the 40% you don't find might 829 00:40:27,740 --> 00:40:29,960 be the ones that have the bigger effect. 830 00:40:29,960 --> 00:40:32,320 They might be the one that have moved to London, because 831 00:40:32,320 --> 00:40:34,300 of the extra education they are getting. 832 00:40:34,300 --> 00:40:37,700 So then they decided, let's take a smaller number of kids, 833 00:40:37,700 --> 00:40:40,060 and track them wherever they are. 834 00:40:40,060 --> 00:40:41,780 Really find them. 835 00:40:41,780 --> 00:40:43,750 And when you do that, they found a quite a 836 00:40:43,750 --> 00:40:44,760 large number of them. 837 00:40:44,760 --> 00:40:49,060 So that altogether in the sample, they have about 85% of 838 00:40:49,060 --> 00:40:52,680 tracking rate, in treatment and in 839 00:40:52,680 --> 00:40:55,220 controls very similarly. 840 00:40:55,220 --> 00:40:58,350 So therefore, we can now look at what happened to wages. 841 00:40:58,350 --> 00:41:04,650 So this is the empirical distribution of log wages. 842 00:41:04,650 --> 00:41:20,530 So what this tells you is, roughly, if you 843 00:41:20,530 --> 00:41:22,090 take any line here-- 844 00:41:22,090 --> 00:41:25,020 for example, it says log earning of 7. 845 00:41:25,020 --> 00:41:28,300 So wages tend to be log numbers. 846 00:41:28,300 --> 00:41:31,020 So we like to show logs. 847 00:41:31,020 --> 00:41:36,190 So in the treatment group, about 10% of 848 00:41:36,190 --> 00:41:39,310 people, a log of 7. 849 00:41:39,310 --> 00:41:46,720 And in the control group, that's about 21%, 25%, 850 00:41:46,720 --> 00:41:48,260 something like that. 851 00:41:48,260 --> 00:41:49,770 So what does this mean? 852 00:41:49,770 --> 00:41:55,780 This What happened to the distribution of wage between 853 00:41:55,780 --> 00:41:59,240 treatment and control, and what does this mean? 854 00:41:59,240 --> 00:42:00,490 How do we read this? 855 00:42:04,090 --> 00:42:07,140 You can do it. 856 00:42:07,140 --> 00:42:09,880 You've seen a distribution, any distribution before. 857 00:42:09,880 --> 00:42:11,130 I know that. 858 00:42:13,100 --> 00:42:16,720 Just describe what happens to these two curves. 859 00:42:19,940 --> 00:42:20,780 You, you, you, you. 860 00:42:20,780 --> 00:42:21,900 I was talking to you. 861 00:42:21,900 --> 00:42:23,911 Just describe what happens to these two curves. 862 00:42:27,140 --> 00:42:33,462 Just tell me, physically, what happens to these two curves. 863 00:42:33,462 --> 00:42:34,863 AUDIENCE: [INAUDIBLE]. 864 00:42:34,863 --> 00:42:36,370 PROFESSOR: It moved right. 865 00:42:36,370 --> 00:42:37,346 Right? 866 00:42:37,346 --> 00:42:38,322 AUDIENCE: Yeah. 867 00:42:38,322 --> 00:42:39,220 PROFESSOR: Right? 868 00:42:39,220 --> 00:42:40,540 That was hard. 869 00:42:40,540 --> 00:42:42,240 They moved right. 870 00:42:42,240 --> 00:42:45,150 Now, what is hard is saying, well, now that they move 871 00:42:45,150 --> 00:42:47,100 right, what does this mean? 872 00:42:47,100 --> 00:42:47,677 Noah. 873 00:42:47,677 --> 00:42:50,062 AUDIENCE: Well, I think two things. 874 00:42:50,062 --> 00:42:53,876 Well, first of all, the on average peaks higher, which 875 00:42:53,876 --> 00:42:58,836 means that the distribution in any case, on average, people 876 00:42:58,836 --> 00:42:59,828 [INAUDIBLE]. 877 00:42:59,828 --> 00:43:04,292 And also, it looks like it's narrower, which means that 878 00:43:04,292 --> 00:43:07,268 more people are also earning more, as opposed to just the 879 00:43:07,268 --> 00:43:08,770 average also earning more. 880 00:43:08,770 --> 00:43:09,630 PROFESSOR: Right. 881 00:43:09,630 --> 00:43:12,070 So those two things are exactly true. 882 00:43:12,070 --> 00:43:14,290 So what we see is, number one, here is the peak. 883 00:43:14,290 --> 00:43:19,200 So this is where, in the control group, we get 45% of 884 00:43:19,200 --> 00:43:24,440 people earning about a wage of 8. 885 00:43:24,440 --> 00:43:26,550 That's the mode of the distribution. 886 00:43:26,550 --> 00:43:29,240 Then, the nice thing with wages is they're going to be 887 00:43:29,240 --> 00:43:33,460 log normal, which means that the mode is about the medium. 888 00:43:33,460 --> 00:43:37,910 It also means that 50% of the people in the control group 889 00:43:37,910 --> 00:43:40,750 earn less than 8. 890 00:43:40,750 --> 00:43:44,360 Whereas here, we find that, if we want to find 50% of the 891 00:43:44,360 --> 00:43:49,480 people earning less than something, it's closer. 892 00:43:49,480 --> 00:43:51,720 So for the control group, it's like 7 and 1/2, and the 893 00:43:51,720 --> 00:43:53,930 treatment group is 8. 894 00:43:53,930 --> 00:43:57,520 So in the control group, 50% of people earn less than 7 and 895 00:43:57,520 --> 00:44:00,060 1/2, and in the treatment group, 50% of people 896 00:44:00,060 --> 00:44:02,070 earn less than 8. 897 00:44:02,070 --> 00:44:05,840 And in fact, we could transform this graph into a 898 00:44:05,840 --> 00:44:08,910 cumulative distribution function instead of density. 899 00:44:08,910 --> 00:44:11,310 And we would find that, given this graph, given that it's 900 00:44:11,310 --> 00:44:14,680 nicely shifted to the right and it's also a little bit 901 00:44:14,680 --> 00:44:18,500 less valuable, as Noah pointed out, we would find that at 902 00:44:18,500 --> 00:44:22,250 every percentage, we have more people in the control group 903 00:44:22,250 --> 00:44:25,460 who make less than that at every level. 904 00:44:25,460 --> 00:44:27,850 We have a more people in the control group earning less 905 00:44:27,850 --> 00:44:29,940 than that than in the treatment group. 906 00:44:29,940 --> 00:44:31,170 Which means that-- 907 00:44:31,170 --> 00:44:32,740 Well, it has to mean that the people in the 908 00:44:32,740 --> 00:44:34,710 treatment group earn more. 909 00:44:34,710 --> 00:44:37,800 And not only that, but-- 910 00:44:37,800 --> 00:44:42,120 not every single person, but statistically-- 911 00:44:42,120 --> 00:44:44,500 everybody in the treatment does somewhat better. 912 00:44:44,500 --> 00:44:46,530 So we are saying the distribution in the treatment 913 00:44:46,530 --> 00:44:49,180 group statistically dominates the distribution in the 914 00:44:49,180 --> 00:44:50,650 control group. 915 00:44:50,650 --> 00:44:54,720 If you had to choose which society to live in, without 916 00:44:54,720 --> 00:44:58,540 knowing, you would pick the treatment group. 917 00:44:58,540 --> 00:45:02,005 Because the chance that you are earning more is better in 918 00:45:02,005 --> 00:45:03,450 one place than the other. 919 00:45:03,450 --> 00:45:06,490 So that's what happens with this distribution. 920 00:45:06,490 --> 00:45:09,070 We can just look at them and say, yeah, we have more people 921 00:45:09,070 --> 00:45:12,205 earning less and we have here more people earning more. 922 00:45:15,320 --> 00:45:19,840 So now we can say, well, how does it look like? 923 00:45:19,840 --> 00:45:23,550 This could just all be nice in graph, but there is no 924 00:45:23,550 --> 00:45:24,490 standard error here. 925 00:45:24,490 --> 00:45:25,730 There is no confidence interval. 926 00:45:25,730 --> 00:45:29,750 Maybe this is not really very solid. 927 00:45:29,750 --> 00:45:32,420 So we can look at that in a regression. 928 00:45:32,420 --> 00:45:35,810 So this is a simple regression, which gives us 929 00:45:35,810 --> 00:45:37,770 directly the difference-- 930 00:45:37,770 --> 00:45:41,760 what you can read here is the difference between the log 931 00:45:41,760 --> 00:45:46,800 earning of the treatment group and the log earning of the 932 00:45:46,800 --> 00:45:48,270 control group. 933 00:45:48,270 --> 00:45:52,250 That means I could have plotted bar charts like we had 934 00:45:52,250 --> 00:45:53,230 with the bednet. 935 00:45:53,230 --> 00:45:57,910 It's saying, this is the mean here. 936 00:45:57,910 --> 00:46:01,550 The mean wage in the control group is 7.8, which 937 00:46:01,550 --> 00:46:04,230 corresponds to above the median and above the mode of 938 00:46:04,230 --> 00:46:06,750 the distribution, 7.8. 939 00:46:06,750 --> 00:46:15,650 And the mean wage for the treatment group is log.18. 940 00:46:15,650 --> 00:46:18,050 So that means about 18-- 941 00:46:18,050 --> 00:46:18,980 19, sorry. 942 00:46:18,980 --> 00:46:21,910 19 percentage points higher than the mean in 943 00:46:21,910 --> 00:46:22,840 the treatment group. 944 00:46:22,840 --> 00:46:26,970 So when we run regression in logs, the advantage is we can 945 00:46:26,970 --> 00:46:28,870 read the coefficient directly as the 946 00:46:28,870 --> 00:46:30,660 percentage point increases. 947 00:46:30,660 --> 00:46:34,010 So if we wanted to know, what's the mean log wages in 948 00:46:34,010 --> 00:46:34,730 the treatment group? 949 00:46:34,730 --> 00:46:37,460 What do we need to do from this graph? 950 00:46:37,460 --> 00:46:39,030 So make sure that you have it well. 951 00:46:41,890 --> 00:46:44,778 Yeah. 952 00:46:44,778 --> 00:46:49,210 AUDIENCE: Take the median and multiply it by 1.19. 953 00:46:49,210 --> 00:46:49,390 PROFESSOR: No. 954 00:46:49,390 --> 00:46:50,640 So what you would do-- 955 00:46:52,960 --> 00:46:55,080 This is the mean of the log. 956 00:46:55,080 --> 00:46:58,430 And this is the log point that they get. 957 00:46:58,430 --> 00:47:02,950 So if we wanted to know the log wages for the treatment 958 00:47:02,950 --> 00:47:09,350 group, all we would need to do is to add 0.19 to 7.8. 959 00:47:09,350 --> 00:47:11,180 So that would be about 8. 960 00:47:11,180 --> 00:47:14,580 And then if we wanted to know the level then we would take 961 00:47:14,580 --> 00:47:16,690 the exponential of 8. 962 00:47:16,690 --> 00:47:17,290 Right? 963 00:47:17,290 --> 00:47:22,005 So when you have experiments, you can just take the mean, 964 00:47:22,005 --> 00:47:24,650 and you can calculate the mean in the treatment group or the 965 00:47:24,650 --> 00:47:26,390 mean the control group. 966 00:47:26,390 --> 00:47:29,600 But in the papers in studies, what you generally see is 967 00:47:29,600 --> 00:47:33,500 people running a very simple, ordinary [INAUDIBLE] square 968 00:47:33,500 --> 00:47:40,390 regression on wages of whether you are a treatment person. 969 00:47:40,390 --> 00:47:43,070 And the way we'll read this is just saying, this is the 970 00:47:43,070 --> 00:47:45,110 difference between treatment and control. 971 00:47:45,110 --> 00:47:47,520 And this is the mean for control. 972 00:47:47,520 --> 00:47:49,870 And then, once we've done that, we can add other things 973 00:47:49,870 --> 00:47:52,920 that absolves the noise, and we'll get 974 00:47:52,920 --> 00:47:54,040 slightly different results. 975 00:47:54,040 --> 00:47:55,740 But not very different, because everything is 976 00:47:55,740 --> 00:47:57,300 randomized. 977 00:47:57,300 --> 00:47:59,214 What is this one? 978 00:47:59,214 --> 00:48:00,590 Over here? 979 00:48:04,794 --> 00:48:06,690 What is this little [INAUDIBLE] 980 00:48:06,690 --> 00:48:07,440 in [INAUDIBLE]? 981 00:48:07,440 --> 00:48:09,200 Sorry? 982 00:48:09,200 --> 00:48:09,990 AUDIENCE: Errors? 983 00:48:09,990 --> 00:48:11,260 PROFESSOR: The standard error. 984 00:48:11,260 --> 00:48:12,210 Exactly. 985 00:48:12,210 --> 00:48:14,180 This guy is the standard error. 986 00:48:14,180 --> 00:48:17,490 So this is saying there is some noise around these wages. 987 00:48:17,490 --> 00:48:20,460 So the difference, the mean, because we have the 988 00:48:20,460 --> 00:48:21,350 distribution of wages. 989 00:48:21,350 --> 00:48:27,760 So there is some variation around the estimate. 990 00:48:27,760 --> 00:48:31,840 And therefore, there is some noise around our estimate of 991 00:48:31,840 --> 00:48:34,660 the difference between treatment and control wages. 992 00:48:34,660 --> 00:48:35,910 And that tells us the standard error. 993 00:48:39,170 --> 00:48:42,630 So now we need to know, well, how do I know whether this 994 00:48:42,630 --> 00:48:47,300 effect is just due to chance, or if it's a real effect. 995 00:48:47,300 --> 00:48:49,100 Once I give you the coefficient, and 996 00:48:49,100 --> 00:48:50,960 the standard error. 997 00:48:50,960 --> 00:48:51,440 Yeah. 998 00:48:51,440 --> 00:48:53,380 AUDIENCE: If it's more than two standard errors, isn't it 999 00:48:53,380 --> 00:48:54,850 significant? 1000 00:48:54,850 --> 00:48:55,770 PROFESSOR: Right. 1001 00:48:55,770 --> 00:48:59,160 So if you divide the coefficient by the standard 1002 00:48:59,160 --> 00:49:02,760 error, it gives you something we call the t-statistic. 1003 00:49:02,760 --> 00:49:06,470 For the hypothesis that the effect is 0. 1004 00:49:06,470 --> 00:49:08,530 So when we divide the coefficient by the standard 1005 00:49:08,530 --> 00:49:14,130 error, we get the t-statistic, and the t-statistic is for the 1006 00:49:14,130 --> 00:49:17,170 test that the coefficient is not 0. 1007 00:49:17,170 --> 00:49:20,190 So the hypothesis is, is this coefficient 0? 1008 00:49:20,190 --> 00:49:27,470 So each test goes with a level of confidence, which is the 1009 00:49:27,470 --> 00:49:30,100 probability of a type one error. 1010 00:49:30,100 --> 00:49:32,900 That is, the probability that you are saying there is an 1011 00:49:32,900 --> 00:49:35,182 effect when in fact, there is not. 1012 00:49:35,182 --> 00:49:36,490 Generally in economics-- 1013 00:49:36,490 --> 00:49:38,660 I don't know in other fields, but in economics-- generally 1014 00:49:38,660 --> 00:49:41,580 we go with sizes of 5%. 1015 00:49:41,580 --> 00:49:45,880 So we accept to say that something has an effect when 1016 00:49:45,880 --> 00:49:49,530 in fact it doesn't with a probability of 5%. 1017 00:49:49,530 --> 00:49:55,420 And 5% corresponds to a t-statistic of 1.96. 1018 00:49:55,420 --> 00:49:59,270 So when you see regression table like this, it's very 1019 00:49:59,270 --> 00:50:01,890 simple if things are randomized. 1020 00:50:01,890 --> 00:50:04,330 When you see a regression, 1021 00:50:04,330 --> 00:50:06,630 looking at these effects, gives you the difference 1022 00:50:06,630 --> 00:50:08,440 between treatment and control. 1023 00:50:08,440 --> 00:50:09,940 Divided by it's standard error. 1024 00:50:09,940 --> 00:50:12,690 And if it's above 1.96, it tells you that the effect is 1025 00:50:12,690 --> 00:50:14,820 significantly different from 0. 1026 00:50:14,820 --> 00:50:16,310 That is, there is a real effect. 1027 00:50:16,310 --> 00:50:18,290 Not an effect due to chance. 1028 00:50:18,290 --> 00:50:21,100 So here of course, it's much above 2. 1029 00:50:21,100 --> 00:50:23,290 And it's about 19%. 1030 00:50:23,290 --> 00:50:27,110 So it tells you that the wage of the treated guys is 19% 1031 00:50:27,110 --> 00:50:29,600 higher than the wage of the control guys. 1032 00:50:29,600 --> 00:50:30,850 Which is a fair amount. 1033 00:50:44,890 --> 00:50:48,280 So why do I say that 19% wage is high? 1034 00:50:55,120 --> 00:50:57,970 What was the economic growth in Kenya over this period, 1035 00:50:57,970 --> 00:50:59,190 give or take? 1036 00:50:59,190 --> 00:51:00,440 An order of magnitude? 1037 00:51:02,830 --> 00:51:04,320 AUDIENCE: 10%? 1038 00:51:04,320 --> 00:51:05,740 PROFESSOR: 10% would be nice. 1039 00:51:05,740 --> 00:51:07,470 [LAUGHTER] 1040 00:51:07,470 --> 00:51:10,000 PROFESSOR: I don't know if they had any single year where 1041 00:51:10,000 --> 00:51:11,250 they had 10% growth. 1042 00:51:14,214 --> 00:51:15,100 AUDIENCE: Like 4? 1043 00:51:15,100 --> 00:51:16,280 PROFESSOR: Yeah, 3 4. 1044 00:51:16,280 --> 00:51:16,650 3, 4. 1045 00:51:16,650 --> 00:51:17,908 AUDIENCE: Do you know what inflation is? 1046 00:51:17,908 --> 00:51:20,790 PROFESSOR: So that would be in real time. 1047 00:51:20,790 --> 00:51:21,110 AUDIENCE: Adjusted. 1048 00:51:21,110 --> 00:51:22,280 All right. 1049 00:51:22,280 --> 00:51:24,810 PROFESSOR: But this is, remember, we are comparing 1050 00:51:24,810 --> 00:51:26,280 treatment to control. 1051 00:51:26,280 --> 00:51:28,460 So there is no inflation here, because our treatment people 1052 00:51:28,460 --> 00:51:31,670 were measured at the same time. 1053 00:51:31,670 --> 00:51:32,890 Take real growth. 1054 00:51:32,890 --> 00:51:37,470 If we are saying 3% to 4% a year, we are being generous to 1055 00:51:37,470 --> 00:51:39,790 Kenya for the average. 1056 00:51:39,790 --> 00:51:43,570 So that means that these guys got the equivalent of several 1057 00:51:43,570 --> 00:51:48,130 years of good economic growth, except there has not been many 1058 00:51:48,130 --> 00:51:51,610 years in Kenya where there has been several years of good 1059 00:51:51,610 --> 00:51:53,790 economic growth. 1060 00:51:53,790 --> 00:51:56,330 So that's why I wanted to get you excited about worms for 1061 00:51:56,330 --> 00:51:58,090 five minutes. 1062 00:51:58,090 --> 00:52:03,000 So this thing corresponds to giving the kids a pill which 1063 00:52:03,000 --> 00:52:06,720 costs about, including the delivery cost and all of that, 1064 00:52:06,720 --> 00:52:11,640 about $0.60 of delivering the pill. 1065 00:52:11,640 --> 00:52:14,090 You need to do that twice a year. 1066 00:52:14,090 --> 00:52:16,590 And this is a difference between doing it for three 1067 00:52:16,590 --> 00:52:18,290 years versus one. 1068 00:52:18,290 --> 00:52:20,780 So this is your investment, it's probably a good 1069 00:52:20,780 --> 00:52:24,590 investment, that was delivered by society here in the form of 1070 00:52:24,590 --> 00:52:28,290 this NGO, was a [INAUDIBLE]. 1071 00:52:28,290 --> 00:52:30,290 And that's 19% per year. 1072 00:52:30,290 --> 00:52:32,910 That's a lot. 1073 00:52:32,910 --> 00:52:35,280 Even people, if they are to do it themselves, maybe they have 1074 00:52:35,280 --> 00:52:38,640 to do to the shop so they don't get it for $0.60. 1075 00:52:38,640 --> 00:52:39,890 They have to pay $1. 1076 00:52:42,030 --> 00:52:45,410 Then they get several years of good growth for the entire 1077 00:52:45,410 --> 00:52:47,140 lifetime of the child. 1078 00:52:47,140 --> 00:52:49,690 So we are talking about, for a lifetime [INAUDIBLE] 1079 00:52:49,690 --> 00:52:53,310 of several thousand dollars of extra wages. 1080 00:52:53,310 --> 00:52:56,280 And we can see it here. 1081 00:52:56,280 --> 00:53:00,770 So what this is is these are the benefits that you're 1082 00:53:00,770 --> 00:53:04,540 getting from this 19% increase in earnings. 1083 00:53:04,540 --> 00:53:08,260 So imagine that you get 19% increase in earnings. 1084 00:53:08,260 --> 00:53:13,130 Take the GDP of Kenya, or the average wage level of Kenya. 1085 00:53:13,130 --> 00:53:14,540 Multiplied by 19%. 1086 00:53:14,540 --> 00:53:16,720 That's how much you're getting every year. 1087 00:53:16,720 --> 00:53:19,900 Then you have to compute the net present value. 1088 00:53:19,900 --> 00:53:24,150 Because the benefit that you're getting if you have to 1089 00:53:24,150 --> 00:53:27,180 pay the investment today, but you're starting to get the 1090 00:53:27,180 --> 00:53:29,660 return when you're 20 and then over your lifetime, it's not 1091 00:53:29,660 --> 00:53:31,330 as valuable. 1092 00:53:31,330 --> 00:53:34,690 So we are using some [INAUDIBLE], let's say 5%. 1093 00:53:34,690 --> 00:53:36,910 And we are computing the net present value of those 1094 00:53:36,910 --> 00:53:40,990 earnings, like we would for the investment in a stock. 1095 00:53:40,990 --> 00:53:46,760 So when you do that, you get over $1,000 increasing in your 1096 00:53:46,760 --> 00:53:47,630 lifetime earnings. 1097 00:53:47,630 --> 00:53:48,482 So this is that. 1098 00:53:48,482 --> 00:53:50,680 And this is how much it cost. 1099 00:53:50,680 --> 00:53:55,980 So you need to deliver the pills, $0.65 per year, and 1100 00:53:55,980 --> 00:53:57,880 then they wanted to-- 1101 00:53:57,880 --> 00:54:03,130 so that would be a huge benefit of, like, $1,500 or 1102 00:54:03,130 --> 00:54:06,310 $1,100 divided by $0.65. 1103 00:54:06,310 --> 00:54:08,770 That would be pretty gigantic. 1104 00:54:08,770 --> 00:54:11,450 That's why worms are exciting. 1105 00:54:11,450 --> 00:54:13,580 Well, they don't want to make it too exciting, so they are 1106 00:54:13,580 --> 00:54:17,300 saying, well, let's see what all the costs we need to add. 1107 00:54:17,300 --> 00:54:19,720 Well, these kids have gone to school a little longer. 1108 00:54:19,720 --> 00:54:21,920 They've gone to school more every year. 1109 00:54:21,920 --> 00:54:25,440 So while in school, they are not playing, or they are not 1110 00:54:25,440 --> 00:54:27,430 earning some wage. 1111 00:54:27,430 --> 00:54:29,510 So they are making some assumption of what is this 1112 00:54:29,510 --> 00:54:31,390 opportunity cost. 1113 00:54:31,390 --> 00:54:33,900 Other wage, unskilled wage. 1114 00:54:33,900 --> 00:54:35,510 All of the day they spend in school, they 1115 00:54:35,510 --> 00:54:38,206 assign them the wage. 1116 00:54:38,206 --> 00:54:40,680 That's an over-estimate, because usually the kids are 1117 00:54:40,680 --> 00:54:42,840 just doing nothing, because they are sick. 1118 00:54:42,840 --> 00:54:44,990 So this is being very generous for the 1119 00:54:44,990 --> 00:54:47,330 cost of being in school. 1120 00:54:47,330 --> 00:54:49,535 And then, they also add the fact that if you have more 1121 00:54:49,535 --> 00:54:52,693 kids in school, you need to have, maybe, a little bit more 1122 00:54:52,693 --> 00:54:53,770 teachers and all that. 1123 00:54:53,770 --> 00:54:56,800 So they also can create how much that can be. 1124 00:54:56,800 --> 00:55:00,340 So these things, you might want to put them, or you might 1125 00:55:00,340 --> 00:55:01,980 not want to put them. 1126 00:55:01,980 --> 00:55:04,820 But the bottom line is that when you do that, this bar is 1127 00:55:04,820 --> 00:55:07,460 pretty huge, and this bar is pretty minimal. 1128 00:55:07,460 --> 00:55:08,408 Yeah. 1129 00:55:08,408 --> 00:55:11,252 AUDIENCE: If they're so clear, why doesn't Kenya's government 1130 00:55:11,252 --> 00:55:12,680 support it? 1131 00:55:12,680 --> 00:55:15,020 PROFESSOR: Well, the answer is they do. 1132 00:55:15,020 --> 00:55:18,810 Because until this study, it wasn't so obvious that the 1133 00:55:18,810 --> 00:55:20,000 benefits are so large. 1134 00:55:20,000 --> 00:55:22,775 Because how would you know? 1135 00:55:22,775 --> 00:55:26,330 You only had those experiments where you were comparing 1136 00:55:26,330 --> 00:55:27,920 people within the same school. 1137 00:55:27,920 --> 00:55:30,490 And you found no effect of deworming. 1138 00:55:30,490 --> 00:55:32,280 So this study came. 1139 00:55:32,280 --> 00:55:34,660 That's an interesting political economic story. 1140 00:55:34,660 --> 00:55:37,520 This study came-- the first one, not even the second one. 1141 00:55:37,520 --> 00:55:39,850 And showed that it basically costs nothing 1142 00:55:39,850 --> 00:55:41,625 to put kids in school. 1143 00:55:41,625 --> 00:55:44,390 The cheapest way to get kids to attend 1144 00:55:44,390 --> 00:55:46,270 to school more regularly. 1145 00:55:46,270 --> 00:55:51,470 So the researchers and us here at Poverty Action have started 1146 00:55:51,470 --> 00:55:54,820 to advertise this as, you might not have thought it that 1147 00:55:54,820 --> 00:55:56,530 way, but deworming is the cheapest way 1148 00:55:56,530 --> 00:55:59,450 to get kids in school. 1149 00:55:59,450 --> 00:56:00,860 We went to Davos. 1150 00:56:00,860 --> 00:56:04,820 Davos is this world congress of rich people. 1151 00:56:04,820 --> 00:56:08,525 And we presented this kind of data, and showed to them, you 1152 00:56:08,525 --> 00:56:11,240 know what, you might not think deworming is so exciting, but 1153 00:56:11,240 --> 00:56:11,920 in fact it is. 1154 00:56:11,920 --> 00:56:13,780 Because it's a great investment. 1155 00:56:13,780 --> 00:56:16,510 So they kind of liked the idea. 1156 00:56:16,510 --> 00:56:17,920 Well, we started an organization 1157 00:56:17,920 --> 00:56:19,330 called deworm the world. 1158 00:56:19,330 --> 00:56:22,140 And started just diffusing these kind of results. 1159 00:56:22,140 --> 00:56:24,440 We didn't even have the wage results yet. 1160 00:56:24,440 --> 00:56:27,080 It was just education results, saying, deworming is a 1161 00:56:27,080 --> 00:56:28,650 sensible education policy. 1162 00:56:28,650 --> 00:56:31,090 It's a very cheap way to get kids in school. 1163 00:56:31,090 --> 00:56:33,920 And started working with the government to get this 1164 00:56:33,920 --> 00:56:35,890 information out. 1165 00:56:35,890 --> 00:56:38,710 One complicated thing with deworming from a political 1166 00:56:38,710 --> 00:56:42,380 economic point of view is that it's a health program that you 1167 00:56:42,380 --> 00:56:44,720 want to do in school. 1168 00:56:44,720 --> 00:56:46,430 The reason why you want to do it in school is you have all 1169 00:56:46,430 --> 00:56:46,770 the kids there. 1170 00:56:46,770 --> 00:56:48,430 That's why it's cheap. 1171 00:56:48,430 --> 00:56:51,430 But when you want to do a health program in school, you 1172 00:56:51,430 --> 00:56:54,630 need the Health Ministry and the Education Ministry to 1173 00:56:54,630 --> 00:56:57,120 collaborate, or you need the Finance Ministry to tell 1174 00:56:57,120 --> 00:56:58,370 them, you do it. 1175 00:56:58,370 --> 00:57:01,760 So that takes some effort, but that effort got done. 1176 00:57:01,760 --> 00:57:05,300 And in fact, in Kenya they are now deworming everywhere. 1177 00:57:05,300 --> 00:57:08,130 So that's millions, millions of children. 1178 00:57:08,130 --> 00:57:10,120 And then this is also moving up and down. 1179 00:57:10,120 --> 00:57:12,550 They're going to start doing it in Bihar, which is a state 1180 00:57:12,550 --> 00:57:14,930 in India where they also have a lot of worms. 1181 00:57:14,930 --> 00:57:16,910 They have started doing it in Andhra Pradesh, where there is 1182 00:57:16,910 --> 00:57:19,570 not that many worms, but they have subregions in Andhra 1183 00:57:19,570 --> 00:57:20,900 Pradesh with a lot of worms. 1184 00:57:20,900 --> 00:57:23,710 And in this way, the information gets out, and 1185 00:57:23,710 --> 00:57:25,275 progressively it's taken up. 1186 00:57:25,275 --> 00:57:27,887 AUDIENCE: In Kenya, did the government sponsor the 1187 00:57:27,887 --> 00:57:30,510 deworming program, or was it outside donors? 1188 00:57:30,510 --> 00:57:36,750 PROFESSOR: In Kenya, the answer is yes and no. 1189 00:57:36,750 --> 00:57:42,090 The direct answer is yes, but it is subsidized in part by 1190 00:57:42,090 --> 00:57:51,720 the Fast Track Initiative, which is international money 1191 00:57:51,720 --> 00:57:55,790 that government can access to do things that help education. 1192 00:57:55,790 --> 00:58:00,110 So Kenya can elect to use Fast Track Initiative money to do 1193 00:58:00,110 --> 00:58:03,890 textbooks, or to do computers in school, or to do 1194 00:58:03,890 --> 00:58:06,160 blackboards, or to pay teachers more. 1195 00:58:06,160 --> 00:58:07,570 And what they did is they took some of 1196 00:58:07,570 --> 00:58:09,960 that money to do deworming. 1197 00:58:09,960 --> 00:58:13,670 The thing is, deworming is cheap enough that once you 1198 00:58:13,670 --> 00:58:16,940 realize that it is a good thing to do, money is less the 1199 00:58:16,940 --> 00:58:20,200 issue than getting everybody on board and organized. 1200 00:58:20,200 --> 00:58:20,450 Yeah. 1201 00:58:20,450 --> 00:58:22,109 AUDIENCE: And so I'm thinking there's probably other 1202 00:58:22,109 --> 00:58:25,190 developing countries that have significantly worm issues. 1203 00:58:25,190 --> 00:58:27,086 And then why aren't those countries doing it? 1204 00:58:27,086 --> 00:58:29,470 You mentioned India, but I'd imagine there's a lot more. 1205 00:58:29,470 --> 00:58:29,960 PROFESSOR: Yes. 1206 00:58:29,960 --> 00:58:35,010 So the answer is slowly, slowly they are getting into 1207 00:58:35,010 --> 00:58:36,070 the bandwagon. 1208 00:58:36,070 --> 00:58:38,440 But that's a very good question, which is, number one 1209 00:58:38,440 --> 00:58:40,470 you need to have the evidence out. 1210 00:58:40,470 --> 00:58:42,720 And until fairly recently, in particular until this 1211 00:58:42,720 --> 00:58:45,150 experiment, the evidence wasn't out. 1212 00:58:45,150 --> 00:58:47,400 And this is not something that people could just 1213 00:58:47,400 --> 00:58:48,720 make up on their own. 1214 00:58:48,720 --> 00:58:51,910 I think in particular, the effect on education, I don't 1215 00:58:51,910 --> 00:58:54,335 think the first thing that comes to an education 1216 00:58:54,335 --> 00:58:57,130 minister, or the first thing that would come to you, if I'd 1217 00:58:57,130 --> 00:58:59,800 asked you in principle, how would you increase education? 1218 00:58:59,800 --> 00:59:01,300 What's the cheapest way to do it? 1219 00:59:01,300 --> 00:59:03,380 I don't think deworming would have been very high on your 1220 00:59:03,380 --> 00:59:04,250 radar screen. 1221 00:59:04,250 --> 00:59:06,600 It's not very high on anybody's radar screen, 1222 00:59:06,600 --> 00:59:08,130 precisely because worms don't kill. 1223 00:59:08,130 --> 00:59:11,030 So people think of HIV as being important, which it is. 1224 00:59:11,030 --> 00:59:12,230 But people don't think of worms. 1225 00:59:12,230 --> 00:59:13,410 So that's the first reason. 1226 00:59:13,410 --> 00:59:17,200 Once the information is out, then it needs to be 1227 00:59:17,200 --> 00:59:17,750 percolated. 1228 00:59:17,750 --> 00:59:20,500 People need to absorb It. 1229 00:59:20,500 --> 00:59:22,500 And I think this is happening, actually. 1230 00:59:22,500 --> 00:59:26,230 This is one of the pretty hopeful stories, in terms of 1231 00:59:26,230 --> 00:59:27,690 that the evidence can make a difference. 1232 00:59:30,915 --> 00:59:33,390 AUDIENCE: I can understand where you argue with 1233 00:59:33,390 --> 00:59:37,350 government about education effects, 1234 00:59:37,350 --> 00:59:38,340 especially in children. 1235 00:59:38,340 --> 00:59:41,310 But when you get something as long as wage 1236 00:59:41,310 --> 00:59:44,280 effects, pretty long time. 1237 00:59:44,280 --> 00:59:49,725 Are you assuming that no other health hazards would offset 1238 00:59:49,725 --> 00:59:55,210 the gains which can be obtained from deworming. 1239 00:59:55,210 --> 00:59:55,460 PROFESSOR: Right. 1240 00:59:55,460 --> 00:59:58,040 So the question is whether I'm assuming that there are no 1241 00:59:58,040 --> 00:59:59,730 other things that will happen. 1242 00:59:59,730 --> 01:00:02,165 And the beauty of this is I'm not assuming anything. 1243 01:00:05,790 --> 01:00:07,010 In fact, I didn't. 1244 01:00:07,010 --> 01:00:11,610 But Ted Miguel and Michael Kremer dewormed 1245 01:00:11,610 --> 01:00:14,400 the children in 1999. 1246 01:00:14,400 --> 01:00:16,610 And then they had the foresight of deciding, we need 1247 01:00:16,610 --> 01:00:19,570 to continue to track them to find out whether or not there 1248 01:00:19,570 --> 01:00:21,500 is a wage effect. 1249 01:00:21,500 --> 01:00:24,120 If you want to know my prior when they started this 1250 01:00:24,120 --> 01:00:27,690 exercise, very honestly, is that you're wasting your time. 1251 01:00:27,690 --> 01:00:29,600 All of these other things will be happening. 1252 01:00:29,600 --> 01:00:31,570 You're never going to find an effect. 1253 01:00:31,570 --> 01:00:35,100 And so when this came up, I was very surprised in a 1254 01:00:35,100 --> 01:00:37,900 positive way. 1255 01:00:37,900 --> 01:00:40,450 But these results were not even used to sell the 1256 01:00:40,450 --> 01:00:42,730 deworming to the government, because we didn't have them 1257 01:00:42,730 --> 01:00:45,210 till very recently. 1258 01:00:45,210 --> 01:00:46,710 Only the education results were used, 1259 01:00:46,710 --> 01:00:48,400 which are very immediate. 1260 01:00:48,400 --> 01:00:50,410 But the point here, you see, you don't assume anything. 1261 01:00:50,410 --> 01:00:53,490 Whatever things would have happened, happened. 1262 01:00:53,490 --> 01:00:55,560 And surprisingly, didn't offset. 1263 01:00:55,560 --> 01:00:57,210 That's what the standard error tells you. 1264 01:01:03,800 --> 01:01:06,510 So deworming is an interesting policy, because it's a good 1265 01:01:06,510 --> 01:01:08,610 policy that's not obviously good. 1266 01:01:08,610 --> 01:01:11,480 So it is nobody's first choice. 1267 01:01:11,480 --> 01:01:13,390 So you have to make it people's first choice. 1268 01:01:13,390 --> 01:01:16,904 The evidence plays a role, and then some convincing. 1269 01:01:16,904 --> 01:01:22,540 And what is interesting is that the parents themselves, 1270 01:01:22,540 --> 01:01:24,520 they could do with them as well. 1271 01:01:24,520 --> 01:01:26,780 And so the second question we want to ask, which is the 1272 01:01:26,780 --> 01:01:29,530 individual version of the same, why don't 1273 01:01:29,530 --> 01:01:30,120 government do it? 1274 01:01:30,120 --> 01:01:32,210 Is why don't parents do it? 1275 01:01:32,210 --> 01:01:34,440 Which is the same question as, why don't people 1276 01:01:34,440 --> 01:01:36,290 buy the fish sauce. 1277 01:01:36,290 --> 01:01:38,630 We'll get to it in a moment, we'll collect the thing. 1278 01:01:38,630 --> 01:01:39,640 Unless you want to have a-- 1279 01:01:39,640 --> 01:01:42,617 AUDIENCE: For deworming, could you just treat the water that 1280 01:01:42,617 --> 01:01:46,030 the children walk in, so that the worms don't go in the 1281 01:01:46,030 --> 01:01:48,560 water, so the kids won't get worms. 1282 01:01:48,560 --> 01:01:50,170 PROFESSOR: So the question is, could you treat the water 1283 01:01:50,170 --> 01:01:51,370 instead of treating the kids? 1284 01:01:51,370 --> 01:01:53,370 I think that's an excellent idea, because you could do it. 1285 01:01:53,370 --> 01:01:56,303 Except that Lake Victoria is really big. 1286 01:01:56,303 --> 01:02:00,440 So I think for Lake Victoria it would be a bit difficult. 1287 01:02:00,440 --> 01:02:01,920 It's really, really big. 1288 01:02:01,920 --> 01:02:04,895 It's almost like a freshwater sea in the middle. 1289 01:02:04,895 --> 01:02:06,200 AUDIENCE: It's not just a lake, right? 1290 01:02:06,200 --> 01:02:08,802 It's also puddles and things like that. 1291 01:02:08,802 --> 01:02:11,628 People walking through there with no shoes. 1292 01:02:11,628 --> 01:02:12,100 PROFESSOR: Yeah. 1293 01:02:12,100 --> 01:02:18,100 It's any body of fresh water that creates the problem. 1294 01:02:18,100 --> 01:02:21,130 So that's general nutrition. 1295 01:02:21,130 --> 01:02:22,970 There are other examples of effective [INAUDIBLE] 1296 01:02:22,970 --> 01:02:23,700 of nutrition. 1297 01:02:23,700 --> 01:02:26,750 But now let's skip to the third one, which is the 1298 01:02:26,750 --> 01:02:29,260 nutrition in the womb, which is what you were asking. 1299 01:02:29,260 --> 01:02:31,610 Whether it's not even more important to feed 1300 01:02:31,610 --> 01:02:32,930 the pregnant woman. 1301 01:02:32,930 --> 01:02:35,180 And the answer is that it is. 1302 01:02:35,180 --> 01:02:40,250 So there is a doctor in the UK called Dr. Barker who this 1303 01:02:40,250 --> 01:02:41,765 hypothesis has his name. 1304 01:02:41,765 --> 01:02:43,730 It's called the Barker Hypothesis. 1305 01:02:43,730 --> 01:02:47,030 What he found is that basically, he found that the 1306 01:02:47,030 --> 01:02:51,120 region which had the highest child mortality, infant 1307 01:02:51,120 --> 01:02:53,660 mortality, neo-natal mortality, were also the 1308 01:02:53,660 --> 01:02:57,110 places where people, once they were born, had the lowest life 1309 01:02:57,110 --> 01:02:58,080 expectancy. 1310 01:02:58,080 --> 01:03:02,080 And he concluded that this was a sign that your condition of 1311 01:03:02,080 --> 01:03:04,180 life in utero were really important. 1312 01:03:04,180 --> 01:03:06,090 Of course, that was not convincing at all, because the 1313 01:03:06,090 --> 01:03:09,920 regions that have the highest infant mortality also are 1314 01:03:09,920 --> 01:03:12,220 pretty bad in many other respects. 1315 01:03:12,220 --> 01:03:15,110 And you will expect that these people live less long. 1316 01:03:15,110 --> 01:03:18,620 But still, he's the first one who formulated the hypothesis. 1317 01:03:18,620 --> 01:03:21,530 And despite the fact that his evidence was weak for it, the 1318 01:03:21,530 --> 01:03:25,150 hypothesis was right, as we subsequently discovered. 1319 01:03:25,150 --> 01:03:28,450 I'm going to give you a few examples where it was seen 1320 01:03:28,450 --> 01:03:29,620 very clearly. 1321 01:03:29,620 --> 01:03:32,700 One of the big names in this is an economist at Colombia 1322 01:03:32,700 --> 01:03:34,740 named Doug Almond. 1323 01:03:34,740 --> 01:03:38,470 And the first thing that Doug Almond found is that he looked 1324 01:03:38,470 --> 01:03:47,390 at people who were born just after 1918, which is the 1325 01:03:47,390 --> 01:03:51,510 period where there was a big, big flew epidemic in the US. 1326 01:03:51,510 --> 01:03:54,250 So many people died of the flu. 1327 01:03:54,250 --> 01:03:55,710 Adults died of the flu. 1328 01:03:55,710 --> 01:03:58,450 But many people didn't, and still had it. 1329 01:03:58,450 --> 01:04:01,370 And in particular, a lot of kids were born from moms who 1330 01:04:01,370 --> 01:04:03,260 had had the flu. 1331 01:04:03,260 --> 01:04:10,480 And the paper here was very simple, which was to compare 1332 01:04:10,480 --> 01:04:15,090 the life outcomes of people who were in utero during the 1333 01:04:15,090 --> 01:04:16,540 period of the flu. 1334 01:04:16,540 --> 01:04:19,430 He doesn't even know whether their mother had the flu. 1335 01:04:19,430 --> 01:04:23,340 It just makes it quite likely that their mother had the flu 1336 01:04:23,340 --> 01:04:26,570 if they were born during that period. 1337 01:04:26,570 --> 01:04:29,360 And they found that children who were in this period during 1338 01:04:29,360 --> 01:04:33,000 the big flu pandemics were sicker as adults. 1339 01:04:33,000 --> 01:04:35,260 They were more likely to have all sorts of diseases. 1340 01:04:35,260 --> 01:04:36,700 Name a disease, they have it. 1341 01:04:36,700 --> 01:04:38,450 Or they are more likely to have it. 1342 01:04:38,450 --> 01:04:39,680 They were earning less money. 1343 01:04:39,680 --> 01:04:42,840 They were less likely to have gone to college. 1344 01:04:42,840 --> 01:04:45,630 And they died earlier, they died younger. 1345 01:04:45,630 --> 01:04:48,330 So that was one of the first people. 1346 01:04:48,330 --> 01:04:52,290 So particularly if your mom had the flu when you were in 1347 01:04:52,290 --> 01:04:53,420 utero, that's not good. 1348 01:04:53,420 --> 01:04:55,450 That's not nutrition. 1349 01:04:55,450 --> 01:04:56,640 Other effects-- 1350 01:04:56,640 --> 01:04:58,620 still a paper by Doug Almond-- 1351 01:04:58,620 --> 01:05:03,420 is that people who are born during or just after the 1352 01:05:03,420 --> 01:05:04,410 Chinese famine-- 1353 01:05:04,410 --> 01:05:08,780 or even just after is a better number. 1354 01:05:08,780 --> 01:05:11,280 Children who are born just after the Chinese famine, so 1355 01:05:11,280 --> 01:05:14,200 who were in utero during the famine, they of 1356 01:05:14,200 --> 01:05:16,380 course live less long. 1357 01:05:16,380 --> 01:05:17,300 They are shorter. 1358 01:05:17,300 --> 01:05:19,290 They have lower wages. 1359 01:05:19,290 --> 01:05:23,710 And even the children of the children of these people are 1360 01:05:23,710 --> 01:05:26,650 shorter and doing less well in life. 1361 01:05:26,650 --> 01:05:29,810 So there is even a second generation that's let's 1362 01:05:29,810 --> 01:05:32,300 productive, fertile, et cetera if you 1363 01:05:32,300 --> 01:05:35,610 were born in the famine. 1364 01:05:35,610 --> 01:05:38,430 There is, of course, a bias in this, when we look at the 1365 01:05:38,430 --> 01:05:40,860 children who were born just after the famine. 1366 01:05:40,860 --> 01:05:42,110 Which comes from what? 1367 01:05:46,137 --> 01:05:48,265 AUDIENCE: They probably also experienced ramifications of 1368 01:05:48,265 --> 01:05:50,400 the famine afterwards. 1369 01:05:50,400 --> 01:05:50,580 PROFESSOR: Right. 1370 01:05:50,580 --> 01:05:52,690 So it was afterwards. 1371 01:05:52,690 --> 01:05:55,280 The famine was very brutal, and ended and 1372 01:05:55,280 --> 01:05:56,840 started very brutally. 1373 01:05:56,840 --> 01:05:59,560 So we might expect that there is not so much effect after. 1374 01:05:59,560 --> 01:06:03,030 That but on the other hand, what do you expect happens 1375 01:06:03,030 --> 01:06:04,280 during the famine? 1376 01:06:07,874 --> 01:06:09,216 AUDIENCE: Probably disease. 1377 01:06:09,216 --> 01:06:10,950 PROFESSOR: A lot of diseases in particular. 1378 01:06:10,950 --> 01:06:12,810 A lot of adults died. 1379 01:06:12,810 --> 01:06:15,790 We are talking about 59 million adults dying. 1380 01:06:15,790 --> 01:06:19,450 And a lot of people probably were never born. 1381 01:06:19,450 --> 01:06:23,360 And in particular, there were stillborns or miscarriages. 1382 01:06:23,360 --> 01:06:26,570 So the people who made it despite the fact that they 1383 01:06:26,570 --> 01:06:29,430 were in utero doing this period, the babies who managed 1384 01:06:29,430 --> 01:06:32,210 to get born are probably pretty good genetic potential 1385 01:06:32,210 --> 01:06:33,990 to start with. 1386 01:06:33,990 --> 01:06:37,500 And despite that, they are doing much less well in life. 1387 01:06:37,500 --> 01:06:40,420 So there is a bias, but it goes in the direction of not 1388 01:06:40,420 --> 01:06:42,150 finding an effect of the famine. 1389 01:06:42,150 --> 01:06:44,630 Because surviving during the famine already indicates that 1390 01:06:44,630 --> 01:06:48,067 you're a pretty feisty child. 1391 01:06:48,067 --> 01:06:50,490 So that's quite extreme. 1392 01:06:50,490 --> 01:06:53,460 You would say, yes, of course being in utero during a famine 1393 01:06:53,460 --> 01:06:54,410 is a bad idea. 1394 01:06:54,410 --> 01:06:56,780 You should avoid it at all costs if you can. 1395 01:06:56,780 --> 01:07:00,170 But maybe it's not particularly relevant. 1396 01:07:00,170 --> 01:07:02,580 Because after all, we are not talking about famine for most 1397 01:07:02,580 --> 01:07:03,140 poor people. 1398 01:07:03,140 --> 01:07:06,490 We are talking about malnutrition and 1399 01:07:06,490 --> 01:07:08,020 ill-nutrition. 1400 01:07:08,020 --> 01:07:11,220 So here is one example of that. 1401 01:07:11,220 --> 01:07:18,270 Is that children who were in utero during Ramadan-- 1402 01:07:18,270 --> 01:07:22,610 and Ramadan shifts, so it's not a particular season. 1403 01:07:22,610 --> 01:07:25,490 So we can look at kids who were in utero doing Ramadan 1404 01:07:25,490 --> 01:07:27,780 who were born in September, who were born in October, who 1405 01:07:27,780 --> 01:07:28,890 were born in December. 1406 01:07:28,890 --> 01:07:30,935 All over the year. 1407 01:07:30,935 --> 01:07:33,550 This is a paper that looks at Uganda. 1408 01:07:33,550 --> 01:07:40,190 Children born of Muslim mothers and who were in utero 1409 01:07:40,190 --> 01:07:42,510 during Ramadan, in particular in the first trimester of 1410 01:07:42,510 --> 01:07:46,780 pregnancy during the Ramadan, are less educated. 1411 01:07:49,460 --> 01:07:54,220 It's many less educated and earn less as adults. 1412 01:07:54,220 --> 01:08:00,620 And with Ramadan, it's not even that you are not eating. 1413 01:08:00,620 --> 01:08:02,280 You're not eating during the day. 1414 01:08:02,280 --> 01:08:03,670 But people eat during the night. 1415 01:08:03,670 --> 01:08:06,990 But these long periods of fasting are no good. 1416 01:08:06,990 --> 01:08:11,830 That's interesting, because you don't have to observe 1417 01:08:11,830 --> 01:08:14,760 Ramadan when you're pregnant. 1418 01:08:14,760 --> 01:08:16,380 You could not do it. 1419 01:08:16,380 --> 01:08:18,439 And if you're really observant, in fact, you have 1420 01:08:18,439 --> 01:08:22,229 the option of not doing it and doing it later. 1421 01:08:22,229 --> 01:08:28,300 But pregnant women tend to do Ramadan anyway because other 1422 01:08:28,300 --> 01:08:29,795 people around them do it. 1423 01:08:29,795 --> 01:08:32,569 And what is interesting here is that, in terms of policy 1424 01:08:32,569 --> 01:08:37,569 implication, it could be encouraged to say, you can not 1425 01:08:37,569 --> 01:08:38,680 observe the Ramadan. 1426 01:08:38,680 --> 01:08:42,790 Not everybody does it because it's acceptable not to observe 1427 01:08:42,790 --> 01:08:44,340 it, potentially. 1428 01:08:44,340 --> 01:08:45,910 But most women do. 1429 01:08:45,910 --> 01:08:51,939 And this is not good for their children. 1430 01:08:51,939 --> 01:08:55,490 And even though it's not something massive, it's this 1431 01:08:55,490 --> 01:08:56,519 shift in the consumption. 1432 01:08:56,519 --> 01:09:00,390 The calories probably stay relatively constant. 1433 01:09:00,390 --> 01:09:03,439 Another example-- which, again, is nothing extreme-- 1434 01:09:03,439 --> 01:09:08,149 the paper by Erica Field and Maximo Torero, which looks at 1435 01:09:08,149 --> 01:09:11,720 one particular micronutrient, which is iodine. 1436 01:09:11,720 --> 01:09:20,029 So iodine deficiency in adulthood create this thyroid 1437 01:09:20,029 --> 01:09:23,170 insuffiency, so it makes you a bit slow. 1438 01:09:23,170 --> 01:09:26,569 So in French, the expression "cretin" comes from that. 1439 01:09:26,569 --> 01:09:31,170 In French, we say "cretin of the Alps," because people from 1440 01:09:31,170 --> 01:09:33,130 the Alps were very far from the sea. 1441 01:09:33,130 --> 01:09:35,529 So their salt came from the mountain, not from the sea. 1442 01:09:35,529 --> 01:09:36,790 So it wasn't iodized. 1443 01:09:36,790 --> 01:09:41,180 So you had more thyroid problems due to iodine 1444 01:09:41,180 --> 01:09:44,240 deficiency in the Alps and elsewhere. 1445 01:09:44,240 --> 01:09:51,010 So now, iodized salt is available on a large scale. 1446 01:09:51,010 --> 01:09:53,630 But before that, when it was not available on a large 1447 01:09:53,630 --> 01:09:56,820 scale, at some point governments realized this 1448 01:09:56,820 --> 01:09:59,620 problem and tried to have programs of 1449 01:09:59,620 --> 01:10:01,310 distribution of iodine. 1450 01:10:01,310 --> 01:10:03,690 And what these people look at is they look at the program in 1451 01:10:03,690 --> 01:10:08,150 Tanzania, which attempted to reach every pregnant woman, 1452 01:10:08,150 --> 01:10:09,680 but failed. 1453 01:10:09,680 --> 01:10:12,650 So some kids, normally you would have five 1454 01:10:12,650 --> 01:10:15,310 waves of the program. 1455 01:10:15,310 --> 01:10:19,770 A pill is sufficient for several months. 1456 01:10:19,770 --> 01:10:23,220 So they were attempting to reach people frequently enough 1457 01:10:23,220 --> 01:10:27,100 that all the pregnant woman would have a pill covering 1458 01:10:27,100 --> 01:10:29,090 them for the duration of the pregnancy. 1459 01:10:29,090 --> 01:10:31,590 But they failed to do that because they were not 1460 01:10:31,590 --> 01:10:32,810 particularly organized. 1461 01:10:32,810 --> 01:10:35,410 So in some districts they went in sometimes, and some 1462 01:10:35,410 --> 01:10:37,460 district they went in some other times. 1463 01:10:37,460 --> 01:10:41,850 So what you can look is kids who were lucky enough to be in 1464 01:10:41,850 --> 01:10:45,030 utero when their mother was covered. 1465 01:10:45,030 --> 01:10:48,345 Compared to kids who were not lucky, and who where in utero, 1466 01:10:48,345 --> 01:10:50,410 in particular first trimester, when 1467 01:10:50,410 --> 01:10:52,430 their mom was not covered. 1468 01:10:52,430 --> 01:10:56,270 And what they look at is education down the line. 1469 01:10:56,270 --> 01:10:59,590 And they found that the covered kids have about a 1470 01:10:59,590 --> 01:11:04,280 third of a year more education than the uncovered kids, for 1471 01:11:04,280 --> 01:11:07,710 receiving this iodine supplementation. 1472 01:11:07,710 --> 01:11:11,380 So again, a pretty small intervention makes a big 1473 01:11:11,380 --> 01:11:14,300 effect down in life. 1474 01:11:14,300 --> 01:11:18,010 So all of these create potential for poverty traps, 1475 01:11:18,010 --> 01:11:19,300 because if the poor-- 1476 01:11:19,300 --> 01:11:21,570 these are investments that are not costly and 1477 01:11:21,570 --> 01:11:24,270 that have high return. 1478 01:11:24,270 --> 01:11:27,940 Even micronutrients for adults, childhood pregnancy, 1479 01:11:27,940 --> 01:11:28,590 in this order. 1480 01:11:28,590 --> 01:11:32,090 You are asking, pregnancy is a very short period of time. 1481 01:11:32,090 --> 01:11:34,730 Then it will affect the child for their entire life. 1482 01:11:34,730 --> 01:11:38,000 So if the poor are less likely to undertake the investment, 1483 01:11:38,000 --> 01:11:40,370 then there is a potential for a poverty trap here. 1484 01:11:44,510 --> 01:11:46,855 So is it the case that the poor are likely to undertake 1485 01:11:46,855 --> 01:11:48,430 this investment? 1486 01:11:48,430 --> 01:11:50,710 And the answer is yes. 1487 01:11:50,710 --> 01:11:52,930 Most of the poor still consume a diet that's 1488 01:11:52,930 --> 01:11:55,300 very poor in Iran. 1489 01:11:55,300 --> 01:11:57,670 The vast majority of the quarter of the world's 1490 01:11:57,670 --> 01:12:02,370 children who should get worms are still not dewormed. 1491 01:12:02,370 --> 01:12:05,820 The WHO estimates that 40% of pregnant women 1492 01:12:05,820 --> 01:12:08,170 worldwide are anemic. 1493 01:12:08,170 --> 01:12:09,960 Not all of that is due continue to iron deficiency 1494 01:12:09,960 --> 01:12:12,660 anemia, but probably at least a half. 1495 01:12:12,660 --> 01:12:18,040 So these are three examples of saying, these investments are 1496 01:12:18,040 --> 01:12:21,720 not undertaken, even though they are potentially highly 1497 01:12:21,720 --> 01:12:22,970 productive. 1498 01:12:24,610 --> 01:12:26,730 And so you are saying, well, maybe it's not undertaken, but 1499 01:12:26,730 --> 01:12:28,440 it's not because of poverty. 1500 01:12:28,440 --> 01:12:30,800 So is money an issue? 1501 01:12:30,800 --> 01:12:34,470 And it does seem to be that a very small cost, even a very 1502 01:12:34,470 --> 01:12:36,570 small cost, seems to discourage people. 1503 01:12:39,320 --> 01:12:41,260 Asking the question that you were asking before. 1504 01:12:41,260 --> 01:12:42,800 At the level of government. 1505 01:12:42,800 --> 01:12:47,350 If 45 fish sauce costs only $6, it seems the investment is 1506 01:12:47,350 --> 01:12:52,441 worthwhile, and yet no poor family does it. 1507 01:12:52,441 --> 01:12:56,200 In Kenya, in the deworming program, in the first group of 1508 01:12:56,200 --> 01:12:58,760 schools, at some point the NGO wanted to do 1509 01:12:58,760 --> 01:13:00,750 the sustainable thing. 1510 01:13:00,750 --> 01:13:05,420 And the sustainable thing was to ask people to cost-share. 1511 01:13:05,420 --> 01:13:09,250 So they had to pay a little fee for their children. 1512 01:13:09,250 --> 01:13:11,630 Small fee for the entire family. 1513 01:13:11,630 --> 01:13:14,530 And this is believed to be help maintaining 1514 01:13:14,530 --> 01:13:17,270 the program, et cetera. 1515 01:13:17,270 --> 01:13:20,240 The moment where they introduced the cost sharing, 1516 01:13:20,240 --> 01:13:22,720 the take up of the program went to zero. 1517 01:13:22,720 --> 01:13:24,130 Nobody took it up. 1518 01:13:24,130 --> 01:13:25,495 So that goes back to this. 1519 01:13:25,495 --> 01:13:27,550 They didn't know the effect, maybe. 1520 01:13:27,550 --> 01:13:30,290 Interestingly, it means asking people to pay is not 1521 01:13:30,290 --> 01:13:30,880 sustainable. 1522 01:13:30,880 --> 01:13:33,940 Because it's the costlier thing about the deworming 1523 01:13:33,940 --> 01:13:37,650 program is to drive your car to the place. 1524 01:13:37,650 --> 01:13:39,020 So once you're there, you want to do all 1525 01:13:39,020 --> 01:13:40,300 many people as possible. 1526 01:13:40,300 --> 01:13:43,910 So if the take up falls down to zero, you've really lost a 1527 01:13:43,910 --> 01:13:46,940 lot of chances. 1528 01:13:46,940 --> 01:13:48,110 Another example. 1529 01:13:48,110 --> 01:13:49,280 It's not only money. 1530 01:13:49,280 --> 01:13:50,320 The thing is that it's not only 1531 01:13:50,320 --> 01:13:51,630 money that is the problem. 1532 01:13:51,630 --> 01:13:56,280 So it's not only poverty, as in lack of income. 1533 01:13:56,280 --> 01:14:01,410 Because in India, we tried something so to fight anemia. 1534 01:14:01,410 --> 01:14:02,400 We said, OK, fine. 1535 01:14:02,400 --> 01:14:06,100 People are not going to buy iron pills. 1536 01:14:06,100 --> 01:14:11,410 But let's introduce a program where the local miller who 1537 01:14:11,410 --> 01:14:15,580 mills the grain of everyone, will add the iron. 1538 01:14:15,580 --> 01:14:19,410 But we only had money to install the machine and pay 1539 01:14:19,410 --> 01:14:24,150 the miller to do it for one minute a village. 1540 01:14:24,150 --> 01:14:26,580 And what we saw is that-- 1541 01:14:26,580 --> 01:14:29,620 so people who were already walking with that miller 1542 01:14:29,620 --> 01:14:31,644 continue to do so. 1543 01:14:31,644 --> 01:14:33,350 But the other people didn't switch. 1544 01:14:36,750 --> 01:14:39,260 So the people who happened to be close by 1545 01:14:39,260 --> 01:14:41,120 benefited from the program. 1546 01:14:41,120 --> 01:14:44,810 But no one was willing to work the extra five minutes to 1547 01:14:44,810 --> 01:14:46,540 benefit from the program. 1548 01:14:46,540 --> 01:14:49,905 And moreover, the miller thought it was a lot of effort 1549 01:14:49,905 --> 01:14:52,030 to add the iron. 1550 01:14:52,030 --> 01:14:54,935 So even though the rules were you're supposed to do it 1551 01:14:54,935 --> 01:14:58,130 unless the family asks, they switched to do the opposite, 1552 01:14:58,130 --> 01:14:59,390 which is you're supposed-- 1553 01:14:59,390 --> 01:15:02,380 they wouldn't not do it if the family didn't ask. 1554 01:15:02,380 --> 01:15:05,435 And the family didn't really ask. 1555 01:15:05,435 --> 01:15:08,630 They didn't say no, but they didn't say yes. 1556 01:15:08,630 --> 01:15:10,950 To the [INAUDIBLE], which was very high at the beginning 1557 01:15:10,950 --> 01:15:14,170 when the miller did it by default, it progressively went 1558 01:15:14,170 --> 01:15:18,300 to a very low number, and the program collapsed. 1559 01:15:18,300 --> 01:15:20,200 Which suggests that it's not only money, 1560 01:15:20,200 --> 01:15:23,270 it's any form of costs. 1561 01:15:23,270 --> 01:15:26,150 Which brings to these other issues. 1562 01:15:26,150 --> 01:15:29,730 One is what Steve said earlier, which is are the 1563 01:15:29,730 --> 01:15:33,270 workers going to reap the benefit, or is the employer 1564 01:15:33,270 --> 01:15:34,950 going to reap the benefit? 1565 01:15:34,950 --> 01:15:38,195 And one sign that it might be the employer rather than the 1566 01:15:38,195 --> 01:15:41,530 worker is that in Indonesia, it's only the wages of the 1567 01:15:41,530 --> 01:15:43,090 self-employed that increased. 1568 01:15:43,090 --> 01:15:44,390 Not the wages, the earnings of the 1569 01:15:44,390 --> 01:15:45,890 self-employed that increased. 1570 01:15:45,890 --> 01:15:50,360 The wages of people working for a wage didn't go up. 1571 01:15:50,360 --> 01:15:51,590 In Kenya, it was different. 1572 01:15:51,590 --> 01:15:53,940 But in Kenya there is all this education effect. 1573 01:15:53,940 --> 01:15:55,830 And one thing that we have in Kenya is that 1574 01:15:55,830 --> 01:15:57,120 people switch sectors. 1575 01:15:57,120 --> 01:16:00,400 The young kids just started workings in different sectors 1576 01:16:00,400 --> 01:16:01,680 altogether. 1577 01:16:01,680 --> 01:16:03,350 But for adults, it's too late for them. 1578 01:16:03,350 --> 01:16:05,790 They're just going to do the same thing a little better. 1579 01:16:05,790 --> 01:16:09,080 And they are not really rewarded for that. 1580 01:16:09,080 --> 01:16:11,140 The other thing are the information things we 1581 01:16:11,140 --> 01:16:13,170 discussed earlier. 1582 01:16:13,170 --> 01:16:15,780 It's very difficult to find out on your own what makes a 1583 01:16:15,780 --> 01:16:18,240 difference and what doesn't. 1584 01:16:18,240 --> 01:16:20,340 Is it iron? 1585 01:16:20,340 --> 01:16:21,870 How do you know that iron matters? 1586 01:16:21,870 --> 01:16:24,580 Until recently, scientists didn't know. 1587 01:16:24,580 --> 01:16:27,010 In the '70s and '80s, scientists were still 1588 01:16:27,010 --> 01:16:29,650 convinced that the big problem was proteins. 1589 01:16:29,650 --> 01:16:31,270 And protein is a problem. 1590 01:16:31,270 --> 01:16:35,400 But they didn't think of micronutrients as an issue. 1591 01:16:35,400 --> 01:16:37,620 So number one, the information is very difficult to acquire. 1592 01:16:37,620 --> 01:16:39,750 So you need to trust outsider. 1593 01:16:39,750 --> 01:16:42,950 It's not very clear you would trust them. 1594 01:16:42,950 --> 01:16:43,490 Finally-- 1595 01:16:43,490 --> 01:16:45,260 and I will finish on that-- 1596 01:16:45,260 --> 01:16:48,330 is that consumption is a decision. 1597 01:16:48,330 --> 01:16:50,500 And people are not machines. 1598 01:16:50,500 --> 01:16:53,140 So they are not maximizing their productivity, they are 1599 01:16:53,140 --> 01:16:55,340 maximizing their utility. 1600 01:16:55,340 --> 01:16:58,650 And their utility is made of other things than our 1601 01:16:58,650 --> 01:17:00,970 productivity can be. 1602 01:17:00,970 --> 01:17:03,910 There is the food that you have to eat every day. 1603 01:17:03,910 --> 01:17:09,630 And if you don't like it, then this is horrible. 1604 01:17:09,630 --> 01:17:13,520 Because eating is the only thing that we are doing day 1605 01:17:13,520 --> 01:17:14,100 in, day out. 1606 01:17:14,100 --> 01:17:17,330 So if we don't like to eat, then it's kind of awful. 1607 01:17:17,330 --> 01:17:21,950 And in particular, this may be one reason why it's 1608 01:17:21,950 --> 01:17:26,760 particularly difficult to have people switch their diet. 1609 01:17:26,760 --> 01:17:28,790 This is something where this is so 1610 01:17:28,790 --> 01:17:30,720 ingrained into our habits. 1611 01:17:30,720 --> 01:17:33,400 And if we are used do eating in a particular way, we may 1612 01:17:33,400 --> 01:17:35,870 know that the best way is to eat something else, but we may 1613 01:17:35,870 --> 01:17:37,900 be very reluctant to switch. 1614 01:17:37,900 --> 01:17:40,250 Now, this is a pattern that we are seeing of course in this 1615 01:17:40,250 --> 01:17:43,430 country, as well as anywhere else. 1616 01:17:43,430 --> 01:17:46,520 The second thing is you may care about your social status. 1617 01:17:46,520 --> 01:17:51,500 Which might be related to how big a party you throw for your 1618 01:17:51,500 --> 01:17:54,850 son's birthday or for your daughter's wedding, or even 1619 01:17:54,850 --> 01:17:57,110 for your dad's funeral. 1620 01:17:57,110 --> 01:18:01,780 Which may be related to some goods you may want to have, 1621 01:18:01,780 --> 01:18:03,360 like a TV or things like that. 1622 01:18:03,360 --> 01:18:06,370 People can care deeply about these things, which may mean 1623 01:18:06,370 --> 01:18:09,450 that they decide to forego nourishing their [INAUDIBLE] 1624 01:18:09,450 --> 01:18:12,620 to make sure that they can actually do the things. 1625 01:18:12,620 --> 01:18:13,820 It's not like-- 1626 01:18:13,820 --> 01:18:16,240 and finally, to diversity of goods you have. 1627 01:18:16,240 --> 01:18:19,490 Like cell phones, TVs, et cetera. 1628 01:18:19,490 --> 01:18:22,200 And all of that means that it has very important policy 1629 01:18:22,200 --> 01:18:23,880 implications, of course. 1630 01:18:23,880 --> 01:18:26,210 Because it means that it's not going to be trivial. 1631 01:18:26,210 --> 01:18:29,720 It's going to eventually be quite difficult to get people 1632 01:18:29,720 --> 01:18:32,400 to convince to switch the type of their diet. 1633 01:18:32,400 --> 01:18:35,470 And also, because of what we saw last time, it's not such a 1634 01:18:35,470 --> 01:18:38,700 great idea to try and subsidized grains 1635 01:18:38,700 --> 01:18:39,500 or things like that. 1636 01:18:39,500 --> 01:18:42,480 Because it's not going to lead to an improvement. 1637 01:18:42,480 --> 01:18:45,240 It's not so much of the quantity of food, because it's 1638 01:18:45,240 --> 01:18:47,050 not that useful to it more. 1639 01:18:47,050 --> 01:18:49,360 Nor in the quality of food, because it's not the fasting 1640 01:18:49,360 --> 01:18:52,140 people will want to do with the extra income. 1641 01:18:52,140 --> 01:18:56,870 That means that you would want to do things that have a 1642 01:18:56,870 --> 01:18:59,230 chance directly to affect the quality of the 1643 01:18:59,230 --> 01:19:00,190 food people are eating. 1644 01:19:00,190 --> 01:19:03,570 And in particular, children and pregnant woman are eating. 1645 01:19:03,570 --> 01:19:06,680 So one is making it as easy as possible to 1646 01:19:06,680 --> 01:19:08,430 do the right thing. 1647 01:19:08,430 --> 01:19:12,140 So invent foods that people want to eat, but the 1648 01:19:12,140 --> 01:19:14,210 micronutrients is in them. 1649 01:19:14,210 --> 01:19:17,660 So there is something called golden rice, which is rice 1650 01:19:17,660 --> 01:19:19,190 which is already fortified in iron. 1651 01:19:19,190 --> 01:19:22,500 But that's GMOs, we might like that or not. 1652 01:19:22,500 --> 01:19:25,620 But it's also like hybrids foods, like yams, which are 1653 01:19:25,620 --> 01:19:28,620 very rich in vitamin A that can grow in Africa. 1654 01:19:28,620 --> 01:19:31,140 So there are organizations that work on this. 1655 01:19:31,140 --> 01:19:34,310 So the organizations that work on this bioengineering-- 1656 01:19:34,310 --> 01:19:36,980 like HarvestPlus, these types of organizations-- 1657 01:19:36,980 --> 01:19:39,410 historically have been focused on making the food more 1658 01:19:39,410 --> 01:19:41,060 productive. 1659 01:19:41,060 --> 01:19:44,410 And what is needed is a shift to making the food 1660 01:19:44,410 --> 01:19:47,150 higher-quality from the point of view of nutrition. 1661 01:19:47,150 --> 01:19:50,660 And this is happening, but slowly, slowly. 1662 01:19:50,660 --> 01:19:55,710 Other thing is when you have the kids, you should invest in 1663 01:19:55,710 --> 01:19:57,420 the quality of their food. 1664 01:19:57,420 --> 01:19:59,640 Because the parents might not know or might not do it. 1665 01:19:59,640 --> 01:20:01,720 But you have the kids right in front of you. 1666 01:20:01,720 --> 01:20:02,530 So it's easy to do. 1667 01:20:02,530 --> 01:20:03,870 So deworming. 1668 01:20:03,870 --> 01:20:05,660 Make the school meal nutritious, for example, by 1669 01:20:05,660 --> 01:20:07,863 sprinkling micronutrient on them. 1670 01:20:07,863 --> 01:20:10,350 And the parents are not going to compensate for that by 1671 01:20:10,350 --> 01:20:12,050 giving them less, because they have no idea what 1672 01:20:12,050 --> 01:20:14,470 you're doing anyway. 1673 01:20:14,470 --> 01:20:17,920 And then you can think of other things. 1674 01:20:17,920 --> 01:20:19,170 I'm going to let you move now.