http://www.techinsider.io/professor-tests-prisoners-dilemma-on-his-students-2015-7
So how did they choose?A professor at the University of Maryland threw his class a curveball when he allowed them to each choose how many extra credit points they wanted to add to their final paper grade.
Sounds generous right? Well, not really.
Here's what Professor Dylan Selterman positioned for his students:
Select whether you want 2 points or 6 points added onto your final paper grade. But there's a small catch: if more than 10% of the class selects 6 points, then no one gets any points.