CIS Working Paper No 48, 2009 Published by the Center for Comparative and International Studies (ETH Zurich and University of Zurich) Who gains from apparentments under D’Hondt? Dr. Daniel Bochsler University of Zurich Universität Zürich Who gains from apparentments under D’Hondt? Daniel Bochsler post-doctoral research fellow Center for Comparative and International Studies Universität Zürich Seilergraben 53 CH-8001 Zürich Switzerland Centre for the Study of Imperfections in Democracies Central European University Nador utca 9 H-1051 Budapest Hungary
[email protected] phone: +41 44 634 50 28 http://www.bochsler.eu Acknowledgements I am in dept to Sebastian Maier, Friedrich Pukelsheim, Peter Leutgäb, Hanspeter Kriesi, and Alex Fischer, who provided very insightful comments on earlier versions of this paper. Manuscript Who gains from apparentments under D’Hondt? Apparentments – or coalitions of several electoral lists – are a widely neglected aspect of the study of proportional electoral systems. This paper proposes a formal model that explains the benefits political parties derive from apparentments, based on their alliance strategies and relative size. In doing so, it reveals that apparentments are most beneficial for highly fractionalised political blocs. However, it also emerges that large parties stand to gain much more from apparentments than small parties do. Because of this, small parties are likely to join in apparentments with other small parties, excluding large parties where possible. These arguments are tested empirically, using a new dataset from the Swiss national parliamentary elections covering a period from 1995 to 2007. Keywords: Electoral systems; apparentments; mechanical effect; PR; D’Hondt. Apparentments, a neglected feature of electoral systems Seat allocation rules in proportional representation (PR) systems have been subject to widespread political debate, and one particularly under-analysed subject in this area is list apparentments.