The distribution of power in governing coalitions of the German Laender

Abstract

In this article, we analyse the distribution of voting power in governing coalitions of the German Laender (states). In a first step, we use the number of votes of parties in a parliament to determine the voting power of the parties. Based on these results, we apply the -power index (Casajus, 2009) to calculate the power of parties within governing coalitions (Wiese, 2007). For this, we consider the limitations of coalition possibilities. In three scenarios, we analyse how these affect the parties’ voting power.

Keywords:

• Banzhaf–Penrose index
• χ-power index
• voting power
• power in governing coalitions

JEL Classification:

• C71
• H1

Notes

¹ With this interpretation, Wiese (2007) introduces the Wiese-power index, which is similar to the -power index.

² In each case, we use the seat distribution after the election of parliaments (data status: 1 September 2011).

³ In NRW, a minority governing coalition is formed by the SPD and the Grüne tolerated by the Linke. For computations, we assume a governing coalition of the three parties.

⁴ Willson (1993) and Housman (2001) did theoretical work on partially defined cooperative games.

⁵ The results for the Saarland are not demonstrated because their calculation seemed to be not very reasonable considering the introduced political exclusions.