Using the integer programming approach introduced by Sethura- man, Teo, and Vohra (2003), we extend the analysis of the preference domains containing an inseparable ordered pair, initiated by Kalai and Ritz (1978). We show that these domains admit not only Ar- rovian social welfare functions...

In the line opened by Kalai and Muller (1977), we explore new con- ditions on preference domains which make it possible to avoid Arrow's impossibility result. In our main theorem, we provide a complete char- acterization of the domains admitting nondictatorial Arrovian social welfare functions...

In a bilateral oligopoly, with large traders, represented as atoms, and small traders, represented by an atomless part, when is there a non-empty intersection between the sets of Walras and Cournot-Nash allocations? Using a two commodity version of the Shapley window model, we show that a...