District magnitude, electoral formula, and the number of parties

• Main Author: BENOIT, Kenneth
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2001
• Subjects: Eastern European Studies; Political Science
• Online Access: https://ink.library.smu.edu.sg/soss_research/4005; https://ink.library.smu.edu.sg/context/soss_research/article/5263/viewcontent/benoit_2001_ejpr_av.pdf
• Institution: Singapore Management University

Duverger's propositions concerning the psychologicaland mechanical consequences of electoral rules have previously beenexamined mainly through the lens of district magnitude,comparing the properties of single-member district pluralityelections with those of multimember proportional representationelections. The empirical consequences of multi-member plurality(MMP) rules, on the other hand, have received scant attention.Theory suggests that the effect of district magnitude on the numberand concentration of parties will differ with regard to whether theallocation rules are plurality-based or proportional. I test thistheory by drawing on a uniquely large-sample dataset where districtmagnitude and electoral formula vary but the basic universe ofpolitical parties is held constant, applying regression analysis todata from several thousand Hungarian local bodies elected in 1994consisting of municipal councils, county councils, and mayors. Theresults indicate that omitting the variable of electoral formula hasthe potential to cause significant bias in estimates of Duvergerianconsequences of district magnitude. In addition, the analysis ofmulti-member plurality elections from the local election datasetreveals counter-intuitively that candidate and party entry mayincrease with district magnitude under MMP, suggesting importantdirections for future investigation of MMP rules.