The Statistical Basis of Decisionmaking in Electoral Districting

Abstract

This paper is concerned with procedures for dividing electorates into constituencies or electoral districts. Two traditions for drawing boundaries are identified, the British procedure of using neutral decisionmakers (Boundary Commissioners), and the American procedure which allows politicians to draw boundaries and thus leads to gerrymandering. If a statistical approach which focuses on the very large number of alternative ways of dividing up an electorate is employed, these two types of decisionmaking can be seen in statistical and political perspective. The most surprising finding of this approach is that in terms of political effects American gerrymanderers and British Boundary Commissioners produce similar types of districting solutions.