We consider a random-matching model in which every agent has a categorization (partition) of his potential opponents. In equilibrium, the strategy of each player i is a best response to the distribution of strategies of his opponents (when they face i) in each category of his categorization. We...

Recent works on political competition incorporate a valence dimension to the standard spatial model. The goal of this paper is to axiomatize rankings of candidates by voters that are consistent with Euclidean preferences on the policy space and an additive valence dimension. Specifically, we...

We consider several ordinal formulations of submodularity, defined for arbitrary binary relations on lattices. Two of these formulations are essentially due to Kreps [Kreps, D.M., 1979. A representation theorem for "Preference for Flexibility". Econometrica 47 (3), 565-578] and one is a...