Forecasting Seats from Votes in British General Elections

Abstract

This article develops a forecasting model of seat shares in the House of Commons applied to general election outcomes. The model utilises past information about party seat shares, together with data from the polls gathered prior to the election, to forecast the number of seats won by the parties. Once it has been estimated the model will be used to make a forecast of the outcome of a possible general election in May 2005. The article starts by focusing on research into translating votes into seats, or the cube rule and its modifications. It then goes on to develop the forecasting model, which is based on electoral and poll data from 1945 to 2001.