Coalitions and Voting Power in the Greek Parliament of 2012: A Case-Study

  • Constandina Koki
  • Stefanos LeonardosEmail author
Research Paper


We revisit the May and June 2012 Greek Parliamentary elections and the December 2014 Presidential election that was held by the June-elected Parliament. The three voting instances provide a political field experiment for the application of power indices and their interpretation in context. We model the Greek Parliament as a weighted majority game and assess voting power with the Shapley–Shubik, Holler and when relevant, Coleman’s indices. Also, based on the actual events, we establish connections between parties and evaluate the Myerson index. We focus on the influence of institutional rules on the distribution of power among the elected political parties and add an alternative input to the ongoing political debate about the reform of both the Parliamentary and Presidential electoral system in Greece. Additionally, our findings contribute to the understanding of the coalition formation process in the particular context and provide empirical evidence on the performance of non-selective indices in parliamentary multi-party settings which can be used for comparison by similar case-studies in the future.


Decision making Weighted voting games Power indices Greece 2012 Elections 

JEL Classification

D7:D72 C7:C71 



We are grateful to the editor Stefan Napel and an anonymous referee for their thoughtful suggestions and detailed comments that helped us to substantially improve our original manuscript. We would also like to thank Manfred Holler, Guido Ortona and Josep Freixas for providing valuable feedback on earlier versions of this paper. The present study would not have been possible without the freely available software ipdirect due to Denis and Robert Leech and AL.EX4 due to Marie-Edith Bissey, Vito Fragnelli and Guido Ortona.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.AUEBAthensGreece
  2. 2.SUTDSingaporeSingapore

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