Pocketbook Voting and Social Preferences in Referenda

We study the role of self-interest and social preferences in referenda. Our analysis is based on collective purchasing decisions of university students on deep-discount flat rate tickets for public transportation and culture. Individual usage data allows quantifying monetary benefits associated with each ticket. We find that turnout is much higher among students who benefit a lot from having a ticket, suggesting instrumental voting. In each referendum, a majority votes in line with self-interest, providing strong evidence for pocketbook voting. However, social preferences like altruism, public good considerations and paternalism shift the vote of a sizable minority against their own financial interest.