The division of social choice theory which attempts to predict how politicians seeking to be elected will interact with voters attempting to vote for their favourite set of policies. The idea derives from the work of economists who tried to explain why shops are located together in the middle of town rather than being spaced equidistantly. By analogy, Anthony Downs argued (in An Economic Theory of Democracy, 1957) that politicians seeking (re‐)election would position themselves on the set of policies favoured by the median voter (see also Black). Spatial theory assumes that voters can measure the distance between themselves and the candidates in multidimensional policy space, and vote either for the candidate nearest them or, tactically, for a more remote candidate with a higher chance of winning.
Like other subdivisions of social choice, spatial theory is usually set out in arcane mathematical language accessible only to other spatial theorists. Thus its strengths and weaknesses are opaque to everybody else. It is inappropriate for use either: