Analyzing the impacts of socio-economic factors on French departmental elections with CoDa methods

ABSTRACT

The vote shares by party on a given subdivision of a territory form a vector called composition (mathematically, a vector belonging to a simplex). It is interesting to model these shares and study the impact of the characteristics of the territorial units on the outcome of the elections. In the political economy literature, few regression models are adapted to the case of more than two political parties. In the statistical literature, there are regression models adapted to share vectors including Compositional Data (CoDa) models, but also Dirichlet models, and others. Our goal is to discuss and illustrate the use CoDa regression models for political economy models for more than two parties. The models are fitted on French electoral data of the 2015 departmental elections.

Keywords:

• Political economy
• multiparty
• compositional regression models
• vote shares
• French departmental election
• Gaussian distribution

Acknowledgments

We thank professor M. Le Breton for introducing us to this topic of political science and for nice discussions. We thank the referees for their comments. Finally, we acknowledge funding from ANR under grant ANR-17-EURE-0010 (Investissements d'Avenir program).

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 https://www.data.gouv.fr/fr/datasets/elections-departementales-2015-resultats-par-bureaux-de-vote/

2 https://www.insee.fr/fr/statistiques

3 http://cartelec.univ-rouen.fr/

4 for more details, see https://fr.wikipedia.org/wiki/Elections_départementales_francaises_de_2015

Additional information

Funding

This work was supported by Agence Nationale de la Recherche [ANR-17-EURE-0010].