Two Limit Views of the Structure of Political Competition

As the number of actors or blocs involved in a competition increases from two to four, so some radically different sets of feasible outcomes (‘spaces’ of competition) are created. From five blocs upwards the competition space is ever-morphing, but within an essentially consistent basic shape. There are two limit views of changes in the competition space. The ‘floorplate’ view is minimalist, focusing only on slots defined by the size of the top two blocs, and treating all other blocs only in aggregate. The equi-probability view is maximalist, assuming that the sizes of all blocs can matter for outcomes. It can be illuminated using a ‘tri-dome’ density map. Any political situation must lie within these limit views. We briefly illustrate two applications - analysing multi-district election outcomes; and the patterning of power scores with qualified majorities. Substantial avenues for further research are indicated.