Vote Trading in Power-Sharing Systems: A Laboratory Investigation
49 Pages Posted: 29 Oct 2018 Last revised: 30 Jan 2020
Date Written: January 30, 2020
Vote trading in power-sharing systems -that is, when a voter's utility with respect to the election's outcome is proportional to the vote share of her favorite party- is, in theory, welfare improving. On the other hand, trading votes for money in majoritarian systems may have detrimental welfare effects, especially when voters' preference intensities are similar (Casella, Llorente-Saguer and Palfrey, 2012). We comparatively test vote trading in these popular electoral systems by the means of a laboratory experiment and find strong evidence in support of the above intuitions: vote trading in power-sharing systems results to higher aggregate welfare across all considered specifications, while it fails to do so in majoritarian ones. Importantly, and unlike what theory predicts, there is a substantial share of subjects who consistently lose from vote trading even in power-sharing systems, indicating that its welfare effects cannot be deemed unambiguous.
Keywords: Vote trading, Power-sharing systems, Majoritarian systems, Experiment, Social welfare
JEL Classification: D72
Suggested Citation: Suggested Citation