We revisit the classic discussion of the comparison between tax and quota, but in a free-entry Cournot oligopoly. We investigate a quantity ceiling regulation as a quota policy. We find that tariff-quota equivalence holds if the firms are symmetric and the number of firms is given exogenously....

We consider a pairwise kidney exchange model. Roth et al. (2005) define priority matchings of the model and introduce a mechanism to derive them. In this paper, we re-examine the priority matching. First, we consider a general priority ordering where multiple patients may hold equal priority. We...