1 00:00:04,660 --> 00:00:06,660 ERIK DEMAINE: Algorithms is an interesting area, 2 00:00:06,660 --> 00:00:11,340 because it's very creative to come up with new algorithms. 3 00:00:11,340 --> 00:00:14,370 There's often many ways to solve the same problem. 4 00:00:14,370 --> 00:00:17,020 But unlike art say, in algorithms 5 00:00:17,020 --> 00:00:21,047 there's a quantifiable measures for how good you did. 6 00:00:21,047 --> 00:00:23,380 What is the running time of the thing you ended up with? 7 00:00:23,380 --> 00:00:25,110 How much space does it use? 8 00:00:25,110 --> 00:00:27,020 It is efficient? 9 00:00:27,020 --> 00:00:30,660 So it's nice in that it's easy to evaluate 10 00:00:30,660 --> 00:00:31,910 whether you kind of succeeded. 11 00:00:31,910 --> 00:00:33,510 Did you get the n log n algorithm? 12 00:00:33,510 --> 00:00:37,090 Did you get the fastest that's possible? 13 00:00:37,090 --> 00:00:41,490 But it's hard to measure a student's understanding 14 00:00:41,490 --> 00:00:44,460 because it's like, did you get the creative trick 15 00:00:44,460 --> 00:00:46,200 that we had in mind, or find another one 16 00:00:46,200 --> 00:00:48,130 that's just as good? 17 00:00:48,130 --> 00:00:50,590 Students may find a different creative trick 18 00:00:50,590 --> 00:00:53,590 that doesn't end up with as good an algorithm in the end. 19 00:00:53,590 --> 00:00:58,650 So we penalize that someone, but for the most part 20 00:00:58,650 --> 00:01:01,230 we are happy when people get correct algorithms. 21 00:01:01,230 --> 00:01:03,290 When they understand the techniques 22 00:01:03,290 --> 00:01:06,270 well enough that they get an algorithm, it's pretty good. 23 00:01:06,270 --> 00:01:09,290 May not be the best, but we consider 24 00:01:09,290 --> 00:01:13,290 that much better than they were using the right technique, 25 00:01:13,290 --> 00:01:15,870 but they ended up using it wrong and so they end up 26 00:01:15,870 --> 00:01:17,780 with something doesn't even work. 27 00:01:17,780 --> 00:01:24,570 And that's much more discouraging, I guess. 28 00:01:24,570 --> 00:01:27,750 But in any case, in a timed exam, 29 00:01:27,750 --> 00:01:31,040 it's really hard to expect students to be creative. 30 00:01:31,040 --> 00:01:33,720 So in that setting, it's hard. 31 00:01:33,720 --> 00:01:35,470 We don't expect a lot of creativity. 32 00:01:35,470 --> 00:01:38,510 We try to keep the questions relatively simple, 33 00:01:38,510 --> 00:01:40,239 so you need just one simple idea. 34 00:01:40,239 --> 00:01:41,780 If you're familiar with the material, 35 00:01:41,780 --> 00:01:42,738 it should come quickly. 36 00:01:42,738 --> 00:01:45,100 It Doesn't always, but-- 37 00:01:45,100 --> 00:01:47,910 So problem sets are definitely an easier way for students 38 00:01:47,910 --> 00:01:49,270 to express creativity. 39 00:01:49,270 --> 00:01:52,880 It gives them a little more time to think about the problem. 40 00:01:52,880 --> 00:01:55,650 Because some problems are going to come easy to some students 41 00:01:55,650 --> 00:01:56,460 and hard to others. 42 00:01:56,460 --> 00:01:58,084 It's going to be different problem set, 43 00:01:58,084 --> 00:02:01,690 so they have a week to think about it. 44 00:02:01,690 --> 00:02:04,170 And also to talk to others, we allow collaboration 45 00:02:04,170 --> 00:02:06,510 in the problem sets, so that makes it easier 46 00:02:06,510 --> 00:02:09,940 to find solutions but still learn a lot from it. 47 00:02:09,940 --> 00:02:11,900 In the exams, it's a lot harder. 48 00:02:11,900 --> 00:02:15,480 In past years we've tried take home exams as a way 49 00:02:15,480 --> 00:02:19,285 to more accurately gauge how creative someone is 50 00:02:19,285 --> 00:02:22,790 in applying these techniques to design new algorithms. 51 00:02:22,790 --> 00:02:25,360 We didn't do that this year. 52 00:02:25,360 --> 00:02:27,485 It's not clear what the right answer is. 53 00:02:27,485 --> 00:02:29,940 It's definitely a challenge in teaching algorithms, 54 00:02:29,940 --> 00:02:33,460 is how to evaluate whether someone can really apply 55 00:02:33,460 --> 00:02:36,600 the techniques in new and creative ways.