Size Invariant Measures of Association: Characterization and Difficulties (with Yves Sprumont) Mathematical Social Sciences, 75 (2015): 115-122.
Minority Representation in Proportional Representation Systems
The paper examines the effect of different forms of proportional representation (PR) on minority representation within Parliaments. We focus on the way candidates are ranked within party lists. Under closed list PR, rankings are decided by party leaders; under open list PR, the electorate determines the ranking by casting votes for individual candi- dates. The paper goes beyond the standard distinction between open and closed list PR by also considering variations in the number of candidates voters can select under the first system. We show that minority representation is lowest under closed list PR and under open list PR when voters can select many candidates within a list. It is highest when voters can only approve a limited number of politicians. This suggests a non-monotonic relationship between voters’ control on the selection of elected candidates and minority representation.
Why do Good Politicians Take Sub-Optimal Decisions?
The paper provides an explanation for sub-optimal policy making decisions by incumbents. We show that electoral incentives can induce them to address less relevant is- sues, disregarding more important ones. This happens even if voters are perfectly informed about issues relevance and politicians are policy oriented. Our explanation relies on the negative correlation between issue importance and probability of solving it: for a given ef- fort exerted by incumbents, less relevant issues guarantee higher probability of success. In equilibrium, the solution of these issues is anyway a positive signal about incumbents’ type. Thus, whenever re-election is sufficiently valuable, politicians prefer not to take the risk of addressing more relevant issues.
An Axiomatic Approach to the Measurement of Ethnic Voting