Quantitative assessment of coalition capacity in the Parliament of Catalonia: power indices in the period 2018–2024

Identifier:  TFG:10235

Handle: https://hdl.handle.net/20.500.11797/TFG10235

Authors:  Rodríguez Mestre, Laia

Abstract:
This study analyzes the distribution of political power in the Parliament of Catalonia during the 2018, 2021, and 2024 legislative terms. The objective is to assess how high levels of parliamentary fragmentation distort the relationship between the parties' nominal weight and their actual strategic influence. Applying cooperative game theory, the Shapley-Shubik, Banzhaf, and Deegan-Packel power indices are calculated, using Python to automate coalition analysis. The results demonstrate that decision-making capacity does not depend on the number of seats held, but rather on the interdependence and marginal utility of each political force within government agreements.