College students have a new superhero team to love. A class of intrepid undergraduate computer science students at Johns Hopkins University decided to collectively outsmart the system and won. According to the NYT, “the grading curve was set by giving the highest score on the final an A, and then adjusting all lower scores accordingly. The students determined that if they collectively boycotted, then the highest score would be a zero, and so everyone would get an A.” The students boycotted the exam by staging a sit-in outside of the classroom for about 20-30 minutes. The protest had to be in person in case someone decided to cross the line and take the exam. If one student took the exam, anyone boycotting would automatically receive a zero. A compelling argument made by the boycott organizer was that student gains nothing by failing his or her classmates.
Personally, I’ve only had a few courses at Temple with this kind of grading policy, but any hopes of collaboration evaporate when you realize that there’s at least one person in the room who won’t trust the rest of the group to boycott. As Catherine Rampell of NYT points out, the boycott is a real-life example of a game with two Nash equilibria. The first Nash equilibrium is that no one takes the exam, with the socially optimal payoff guaranteeing everyone an A. The second is that everyone takes the test, because to boycott without universal participation would guarantee yourself a failing grade. If there was no ability for communication among students, it is overwhelmingly likely that there would be fear of someone cheating, and the loss of being the cheater is less than the loss of being the only cooperator left. The ability for communication breaks some of standard rules for theoretical games, but this is the real world.
The typical real world example for why this never tends to work is the concept of the cartel. If an oligopoly plans to collude and fix prices, then they can increase revenue; however, they are all playing self-interested games in response to others. The most likely result is that one company will cheat to maximize its payoff. The reason the classroom example works differently is because both the individual and social payoff is greatest by not taking the test, a clear focal point. If only this was the grading policy for every class.