We provide a unified approach to imperfect (monopolistic, Bertrand and Cournot) competition equilibria with demand functions derived from symmetric preferences over a large but finite number of goods. The equilibrium markups depend on the Morishima Elasticity of Substitution/Complementarity...

We examine the role of per capita income in closed and open economy models of monopolistic competition based on non-homothetic directly additive preferences a la Dixit-Stiglitz, as in Krugman (1979). In a closed economy with free entry income is always neutral on markups and firm size. In a...

We study monopolistic competition with preferences over differentiated goods characterized by a separable indirect utility rather than a separable direct utility as in the Dixit-Stiglitz model, with the CES case as the only common ground. Examples include linear and log-linear direct demands. In...

We study monopolistic competition under indirect additivity of preferences. This is dual to the Dixit-Stiglitz model, where direct additivity is assumed, with the CES case as the only common ground. Other examples include (perceived) demand functions that are exponential or linear. Our...

A necessary and sufficient condition for an input to be inferior is that, taking into account the input adjustment, an increase of its price raises the marginal productivity of all inputs. Contrary to a widespread opinion, it is not necessary that (some) inputs are “rivals” (i.e., that some...

We reconsider the recent work by [Oku10] on (possibly asymmetric) Cournotian firms with two production factors, one of them being inferior. It is shown there that an increase in the price of the inferior factor does raise equilibrium industry output. In addition of providing a simpler and more...

We study a class of symmetric, quasi-homothetic preferences that result in demands logarithmic in own prices when these have a negligible impact on aggregate price indices (as in monopolistic competition models). Thus marginal revenues are computationally friendly, and decreasing whenever...

According to the so-called Exclusion Principle (introduced by Baye et alii, 1993), it might be profitable for the seller to reduce the number of (fullyinformed) potential bidders in an all-pay auction. We show that the Exclusion Principle does not apply if the seller regards the bidders' private...

We study the equilibrium of the all-pay auction with complete information and a reserve price, and compare it with that of standard auctions. The seller should set a reserve price even when she faces incomplete information. In the latter setting, ex-ante asymmetry among bidders appears necessary...