Mapping election results in proportional electoral systems

Abstract

The paper presents a technique for efficient visualisation of election results in proportional electoral systems. Three cartographic methods (cartogram, inward-oriented buffer and proportional striping) are combined to produce a static map that gives an overview of the distribution of voting power, the electoral abstention and the election results. Unlike the conventional design that shows only the winning subjects, the proposed technique allows reader to analyse the results within a district as well as in the context of the whole country. Regional differences and patterns not present on conventional election maps can be observed. The proposed technique is demonstrated on a map of Slovak parliamentary election held in 2012.