Disclaimer. Don't rely on these old notes in lieu of reading the literature, but they can jog your memory. As a grad student long ago, my peers and I collaborated to write and exchange summaries of political science research. I posted them to a wiki-style website. "Wikisum" is now dead but archived here. I cannot vouch for these notes' accuracy, nor can I say who wrote them.
Dubner and Levitt. 2005. Why vote? A Swiss Turnout-Boosting Experiment (Freakonomics column). New York Times Magazine.
Levitt and Dubner summarize the well-known tension between rational choice models and observed voting behavior. According to economists, you wouldn't vote unless you're mistaken about the probability that your vote matters, mistaken about the costs of voting, or simply wanting to waste time (like we waste money on lotteries). Or, "Perhaps we have been socialized into the voting-as-civic-duty idea, believing that it's a good thing for society if people vote, even if it's not particularly good for the individual. And thus we feel guilty for not voting."
Drawing on the results of a natural experiment in Switzerland, they suggest that voting might be motivated by social rewards: We vote to be seen at the ballot box by our friends and coworkers.
As always, the "Freakonomics" authors don't really contribute anything new or insightful, they merely publicize other scholars' work. In this case, they look at research by Patricia Funk, who studied the introduction of absentee (mail) voting, canton-by-canton, to Switzerland. Although mail voting decreases the costs of voting, turnout went down. The authors conclude that perhaps turnout dropped because those voting by mail fail to gain the social rewards available to those voting in person.
Research on similar subjects