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The Wisdom of Groups by Clyde Freeman Herreid Copyright © 2009, National Science Teachers Association (NSTA). Reprinted with permission from Journal of College CASE STUDY Science Teaching, Vol. 39, No. 2, Nov/Dec 2009. The Wisdom of Groups By Clyde Freeman Herreid ne day in the fall of 1906, the British scientist Fran- cis Galton left his home in the town of Plymouth Oand headed for a country fair. Gal- ton was 85-years-old and beginning to feel his age, but he was still brim- ming with curiosity that had won him renown—and notoriety—for his work on statistics and the science of heredity. And on that particular day, what Galton was curious about was live stock. So begins the first paragraph of a fascinating book, The Wisdom of Crowds, by James Surowiecki (2005). Ase w learn in the following pages, Galton, in his visit to the fair, was captivated by a weight-judging com- petition. A fat ox was on display, and Surowiecki piles on example after works the same way. Populations shift the crowd of onlookers could buy a example of how intelligent crowds can their genotype because of the average ticket to guess the weight of the ani- be smarter than the most knowledge- success of certain phenotypes that mal after it had been slaughtered and able individual. The average guess of carry beneficial alleles. dressed. Farmers, butchers, and just the crowd that estimates the number plain folks were among the 800 souls of jelly beans in a jar is almost always The wisdom of case studies who tried their luck. The best guessers close to perfect. This, Surowiecki ar- All of this brings me to the subject would win prizes. Galton’s interest gues,s i the reason for such unexpected of case studies and how they can be in democracy suggested to him an successes as Wikipedia and Google. taught. Many instructors use small experiment. After the contest was Who could imagine that Wikipedia groups. They use cooperative- or over, he collected the tickets from the would be so accurate given that it collaborative-learning strategies that event organizers, tallied up the values permits anyone to edit everything? have made a major impact on educa- of the guesses, and took their average, The answer turns out to be that when tion in the last 20 years. One of these suspecting that they would be rather people in a crowd make independent methods is problem-based learning, off the mark. Nothing could be further estimates, individual errors and bias formally introduced into medical from the truth. The average guess was are quickly compensated for by con- education about 35 years ago at Mc- 1,197 pounds and the true weight of trary opinions. This system is self- Master University in Ontario, Cana- the slaughtered and dressed ox was correcting. Actually, so is the scientific da. Its use has broadened into under- 1,198 pounds. Galton (1907) wrote in enterprise. No one person controls the graduate education throughout the his paper in Nature, “The result seems outcome. It shares this characteristic world. In medical schools, groups more credible to the trustworthiness with Wikipedia—it is not the wisdom of about 10 students along with a of a democratic judgment than might of an individual that counts so much faculty facilitator try to diagnose a have been expected.” as the wisdom of the crowd. Evolution patient’s problem based on fragmen- 62 Journal of College Science Teaching tary data that are progressively dis- they tend to choose companions that expert individuals at choosing among closed to them over several classes; are much like themselves. Hence, possible alternative solutions (say, meanwhile, they look up and share random groups of students are better. guessing who will win the Super information that might be useful. In Even better, the instructor should cre- Bowl or determining who will be the undergraduate classes, the method ate the groups. next U.S. president), but they are also has morphed a bit; group sizes are My approach to this problem is better at generating possible solu- frequently smaller, and one faculty simple: On the first day of any co- tions to problems (i.e., brainstorm- member may supervise multiple operative learning class, I hand out ing). This is a major argument for a groups. But the same strategy ap- small 3 × 5 index cards for students to democratic government rather than plies: Individuals within teams pool list certain specific information. I ask a dictatorship or oligarchy. their information in order to solve a them to write the following informa- When we look at case study teach- problem. tion: their name, email address, major ing, we find the wisdom of groups is What is it about small groups that field of interest, the courses they have also evident, especially if vigorous makes them so powerful? The answer taken in science, hobby, and grade- discussion is involved. When students is straightforward: Groups tend to point average. Clearly, I can gather the voice their positions, they improve solve problems better than even the latter from their records, but I prefer the chances that they will remember brightest individuals because “many asking them to provide it voluntarily, the key information. But more to the hands make light work,” and “two if they wouldn’t mind. I use this infor- point, discussions are a participatory heads are better than one.” This is mation and their gender and ethnicity form of teaching; new ideas may especially true when the groups are (which I can either see or guess from emerge that no one, not even the in- diverse and individuals act somewhat their names) to sort them into groups structor, has thought of before. independently. of six students. (Groups of six are the Groups don’t always make good largest that I arrange because larger Voting with clickers decisions, of course. Jury trials such groups have a hard time in discussion; This brings me to the notion of click- as the O.J. Simpson case come to an individual is relatively more inhib- ers. One of the most promising tech- mind. When groups go awry, it is itedn i large groups, and they have less nological breakthroughs in teach- often because the members do not “air time” to explain their ideas.) ing in the past 20 years is personal represent a diverse collection of opin- Why this focus on diversity? response systems, better known as ions, or one person, often a putative Once again, it is to seek the broad- “clickers.” These devices, which look leader, has an undue influence on the est possible “landscape” for solu- like TV remote controls, allow an in- group. Thus, the other members are tions. All of this is well-known to structor to survey the thoughts of a not allowed to voice contrary opinions folks in the field of group dynamics. class at any moment. Thus, a lecturer because of coercion or intimidation. Larry Michaelsen, the creator of the can present material for 15 minutes “Group think” predominates. We have small-group learning method called and then ask a multiple-choice ques- situations such as the war room for Team Learning, writes in Team- tion to see if students have followed the Bay of Pigs fiasco in which John Based Learning: A Transformative the presentation. A computer receiv- F. Kennedy’s team was swept along Use of Small Groups (Michaelsen, er picks up student responses and the a disastrous path without contrary Knight, and Fink 2002) that group results are displayed in a histogram advice being given a fair hearing. test scores are typically better than on the projector screen in the front Similarly, it appears that the George the best individual scores. And of the class. Made famous by the W. Bush team’s approach to the inva- Surowiecki (2005), writing in the producers of the TV quiz show Who sion of Iraq may have suffered from Wisdom of Crowds, reminds us that Wants to Be a Millionaire?, click- the same myopia. on the TV show Who Wants to Be ers have made rapid inroads into the One essential lesson to be learned a Millionaire?, when a contestant nation’s classrooms. They are espe- by those of us creating small groups asked the audience to help choose cially useful in large classes in which in our classrooms is this: We should the correct answer to a question, they it is hard to engage students and as not allow individuals to choose their were right 91% of the time, whereas a consequence, attendance can be own groups if we want diversity and “experts” were only right 61% of the miserable. Clickers provide a dra- creativity. When people self-select, time. Groups are not just better than matic antidote to apathy, particularly November/December 2009 63 CASE STUDY when students are awarded points you can fix it by doing some swift References every day if they answer questions backtracking. Galton, F. 1907. Vox populi. Nature 75 correctly. Students say that they are Finally, let me reinforce a state- (1949): 450–452. empowered by clickers and feel like ment I made earlier: There are times Michaelsen, L., A. Knight, and L.D. they are being asked to participate in that groups don’t function well. They Fink, eds. 2002. Team-based learn- the learning process. don’t paint the Mona Lisa, score the ing: A transformative use of small The point that I wish to emphasize opera Carmen, or write War and groups. Westport, CT: Praeger. here is simple. With clickers, when Peace. But they are terrific at col- Surowiecki, J. 2005. The Wisdom of the instructor asks a question, he or lecting data, sifting through them, crowds.
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