A statistical model for Condorcet efficiency based on simulation under spatial model assumptions

This essay evaluates six single-winner, multicandidate electoral systems with respect to their tendency to choose Condorcet candidates. To this end I calibrate a logistic multiple regression model from Monte Carlo simulations, based on a multivariate normal spatial model, in which I vary the number of candidates, number of dimensions, correlation structure, and relative dispersion of candidates and voters. I investigate additional spatial-model variations by comparing further simulation results with predictions of the basic statistical model. The results suggest that for many electoral systems, Condorcet efficiency would increase with perceptual uncertainty of candidates' positions and would be low in a polarized society. Of the voting systems studied, approval voting and the Coombs systems appear least sensitive to variations in assumptions.

[1]  L. Dutter The Structure of Voter Preferences , 1982 .

[2]  Michael H. Kutner Applied Linear Statistical Models , 1974 .

[3]  S. Merrill,et al.  Strategic Voting in Multicandidate Elections under Uncertainty and under Risk , 1981 .

[4]  Peter C. Fishburn,et al.  An analysis of simple two‐stage voting systems , 1976 .

[5]  H. Nurmi Voting Procedures: A Summary Analysis , 1983, British Journal of Political Science.

[6]  Kenneth A. Shepsle,et al.  Politics in plural societies : a theory of democratic instability , 1974, The Journal of Modern African Studies.

[7]  Peter C. Fishburn,et al.  An analysis of voting procedures with nonranked voting , 1977 .

[8]  S. Merrill A Comparison of Efficiency of Multicandidate Electoral Systems , 1984 .

[9]  Robert F. Bordley,et al.  A Pragmatic Method for Evaluating Election Schemes through Simulation , 1983, American Political Science Review.

[10]  Michael X Cohen,et al.  Toward Applicable Social Choice Theory: A Comparison of Social Choice Functions under Spatial Model Assumptions , 1978, American Political Science Review.

[11]  D. F. Morrison,et al.  Multivariate Statistical Methods , 1968 .

[12]  Steven J. Brams,et al.  Strategic information and voting behavior , 1982 .

[13]  John H. Aldrich,et al.  A Method of Scaling with Applications to the 1968 and 1972 Presidential Elections , 1977, American Political Science Review.

[14]  Samuel Merrill,et al.  Strategic decisions under one-stage multi-candidate voting systems , 1981 .