Students get class-wide As by boycotting test, solving Prisoner's Dilemma

Johns Hopkins computer science prof Peter Fröhlich grades his students' tests on a curve — the top-scoring student gets an A, and the rest of the students are graded relative to that brainiac. But last term, his students came up with an ingenious, cooperative solution to this system: they all boycotted the test, meaning that they all scored zero, and that zero was the top score, and so they all got As. The prof was surprisingly cool about it:

Fröhlich took a surprisingly philosophical view of his students' machinations, crediting their collaborative spirit. "The students learned that by coming together, they can achieve something that individually they could never have done," he said via e-mail. "At a school that is known (perhaps unjustly) for competitiveness I didn't expect that reaching such an agreement was possible."

The story of the boycott is a sterling example of how computer networks solve collective action problems — the students solved a prisoner's dilemma in a mutually optimal way without having to iterate, which is impressive:

"The students refused to come into the room and take the exam, so we sat there for a while: me on the inside, they on the outside," Fröhlich said. "After about 20-30 minutes I would give up…. Then we all left." The students waited outside the rooms to make sure that others honored the boycott, and were poised to go in if someone had. No one did, though. Andrew Kelly, a student in Fröhlich's Introduction to Programming class who was one of the boycott's key organizers, explained the logic of the students' decision via e-mail: "Handing out 0's to your classmates will not improve your performance in this course," Kelly said. "So if you can walk in with 100 percent confidence of answering every question correctly, then your payoff would be the same for either decision. Just consider the impact on your other exam performances if you studied for [the final] at the level required to guarantee yourself 100. Otherwise, it's best to work with your colleagues to ensure a 100 for all and a very pleasant start to the holidays."

Fröhlich's changed the grading system — but he's also now offering the students a final project instead of a final exam, should they choose.





Dangerous Curves

[Zack Budryk/Inside Higher Ed]