Interpretation
of Electoral Results: A Bayesian Analysis
José
M.Bernardo
Univ.
de Valencia, Espanha
In
the days which follow a political election, both the media and the politicians
center their discussions on the reallocation of the votes which has taken place
from the last election: who has won votes from whom, who has lost votes to whom.
Typically, the arguments are only more or less informed guesses based on a simple
comparison of the global final results in both elections, with no attempt at a
formal statistical analysis. In this paper, we propose a Bayesian estimation
of the transition probabilities which describe the reallocation of the votes,
based on a hierarchical analysis of the results obtained in both elections in
a selected set of constituencies. The procedure is illustrated with results
obtained at recent Spanish elections.
