Although considerable leverage is gained by modeling a collective actionproblem as a prisoner dilemma game, many, if not most, social problems areonly similar to prisoner dilemma situations. Voting is anexample of a social institution that leads to situations that are veryclose, but not actually, prisoner dilemmas. When one votes, quite clearly,the essence of voting is that the vote one casts will be counted and hencecounts. Although unlikely, it could make a difference; it could change theoutcome.

This possibility, that the vote matters, implies that there is no dominantstrategy. For if one’s vote can matter, then under precisely thosecircumstances, presumably, it pays to vote. Thus, voting is fundamentallydifferent from the standard prisoner dilemma game.

It follows that there is more to be understood about collective action thanwe can model with the prisoner dilemma. And yet, as we shall see, thefundamental similarities between our expanded set of collective action caseshelps us use the tools we have already developed to understand thesituation. Our analysis of simple modifications of these new situationsleads to some surprising results.