Critères pour une meilleure répartition des sièges au sein des structures intercommunales. Une application au cas du Val-d'Oise

The purpose of this paper is to analyze the apportionment of seats in intercommunal structures in the Val-d?Oise region. We compare the observed distribution of the seats to a theoretical one obtained with the Webster?s method (or Saint-Laguë?s method). This comparison is made using the most important power indices in the literature, the Shapley-Shubik index and the Banzhaf index. Assuming that the distance minimisation between populution and power is a good criteria, we show that the observed seats apportionements, the number of seats and the majority rule are not optimal. Classification JEL : C7, D7