Proportional Public Decisions

Abstract

We consider a setting where a group of individuals needs to make a number of independent decisions. The decisions should proportionally represent the views of the voters. We formulate new criteria of proportionality and analyse two rules, Proportional Approval Voting and the Method of Equal Shares, that are inspired by the corresponding approval-based committee election rules. We prove that the two rules provide very strong proportionality guarantees when applied to the setting of public decisions.