Romain Lachat

The Mechanical and Psychological Effects of Electoral Systems A Quasi-Experimental Study

Having two votes for the same election or two simultaneous elections with different electoral systems provides a golden opportunity to ascertain the impact of the electoral system and to sort out the relative magnitude of mechanical and psychological effects on parties and voters. The authors propose a new methodology for estimating such effects and apply that methodology to 13 elections, 9 in Switzerland and 4 in Japan. The authors find mechanical effects to dominate in half of the elections examined, most particularly in the more recent Swiss elections. They discuss the implications of these findings.

Assessing the Mechanical and Psychological Effects of District Magnitude

Abstract District magnitude is a central aspect of the institutional context in PR elections, and it influences parties’ and voters’ strategies. The incentives for strategic behaviour are stronger in smaller districts, as only large parties are likely to be viable. This article investigates how much the vote is affected by this characteristic of the electoral context, focusing on the 2005 and 2009 Portuguese elections. Portugal is one of the countries with the largest degree of variation in district magnitude and represents thus an ideal case for analysing district magnitude effects. Relying on data from the Comparative Study of Electoral Systems, this study shows a strong mechanical effect of district magnitude and a limited psychological effect.

Which way from left to right? On the relation between voters’ issue preferences and left–right orientation in West European democracies:

The left–right scale is the concept most often used to describe citizens’ and parties’ political positions. Its prevalence suggests that political preferences are structured by a single ideological dimension. However, much research shows that citizens’ issue preferences in Western Europe are structured by two dimensions: economic; and social–cultural. How can a single dimension be sufficient to orient oneself in a two-dimensional political space? This article suggests a solution to this paradox: among citizens, the left–right scale and more concrete political issues are related in a non-linear way. Economic issue preferences should be more strongly related to ideological differences among left-wing citizens (e.g. between extreme-left and centre-left citizens) than among right-wing individuals. The reverse pattern should characterize the relation between sociocultural issues and ideological self-placement. The analysis of 28 elections in five West European countries offers strong support for the hypothesis of a non-linear relation.