Free Mobility and the Optimal Number of Jurisdictions

In a free mobility equilibrium with voting for pure public goods within jurisdictions and equal cost sharing, consumers will partition themselves such that high-demand jurisdictions are much larger than low-demand jurisdictions. We compare the welfare implications of a change in the number of jurisdictions. We find in a fairly simple but natural model of a large economy that if one restricts to odd numbers of jurisdictions, a smaller number is better, but among even numbers of jurisdictions the reverse holds. Further, any odd number is preferable to any even number.