0000000001269016
AUTHOR
Yasusada Murata
General Equilibrium Models of Monopolistic Competition: CRRA Versus CARA
We analyze a class of "large group" Chamberlinian monopolistic competition models using multiplicatively quasi-separable (MQS) and additively quasi-separable (AQS) functions. We first prove that the MQS and AQS functions are equivalent to the "constant relative risk aversion" (CRRA) and "constant absolute risk aversion" (CARA) classes of functions, respectively. Whereas both approaches allow for closed-form solutions, only the AQS functions yield profit-maximizing prices that decrease in the mass of competing firms. We then characterize the equilibrium in both cases and discuss some possible applications of the AQS framework to trade, growth, and development.
Gains from Trade and Efficiency under Monopolistic Competition: A Variable Elasticity Case
We present a general equilibrium model of monopolistic competition with variable demand elasticities and investigate the impact of free trade on welfare and efficiency. First, contrary to the constant elasticity case, in which all gains from trade are due to increasing product diversity, our model features gains from pro-competitive effects. Second, we prove that the market outcome is not efficient because too many firms operate at an inefficiently small scale. Last, we illustrate that free trade raises efficiency by reducing the gap between the equilibrium utility and the optimal utility.