This paper with longtime coauthor Geoffrey Pritchard is an important step toward systematic design of electoral systems.

Abstract: Generating realistic artificial preference distributions is an important part of

any simulation analysis of electoral systems. While this has been discussed in some de-

tail in the context of a single electoral district, many electoral systems of interest are based

on districts. Neither treating preferences between districts as independent nor ignoring

the district structure yields satisfactory results. We present a model based on an extension

of the classic Eggenberger-Pólya urn, in which each district is represented by an urn and

there is correlation between urns. We show in detail that this procedure has a small num-

ber of tunable parameters, is computationally efficient, and produces “realistic-looking”

distributions. We intend to use it in further studies of electoral systems.