Selecting a social choice rule : an exploratory panel study

Abstract EN

This study is an attempt to empirically understand public preferences concerning social choice rules.

We focus on four social choice rules (SCRs): Plurality, Plurality with a Run-off, the Majoritarian Compromise (MC) and Borda’s SCR.

We confront our subjects with hypothetical preference profiles of a hypothetical electorate over some abstract set of alternatives at which the four SCRs all disagree and we ask each subject which alternative should be chosen and which should be eliminated for the society whose preference profile is shown.

The study was conducted with 288 subjects who were confronted with five preference profiles each.

We found a very clear support for the MC and Borda’s SCR, the subjects generally not favoring Plurality or Plurality with a Run-off.

We noticed, however, that many of the subjects who chose the alternative which would be chosen by Borda’s SCR were actually choosing it because it coincided with the Social Compromise winner.

As a result, the net outcome of our study is the finding that our subjects strongly favor the MC, then a conglomerate of Borda’s SCR and the SC, strongly disfavoring Plurality and even more so, Plurality with a Run-off.