Too Much Waste: A Failure of Stochastic, Competitive Markets

Abstract

The equilibrium of a competitive market in which firms must choose prices ex ante and demand is stochastic is shown to be second-best inefficient. Even under risk neutrality, equilibrium price exceeds the welfare-maximising predetermined price. Competition tends to eliminate rationing, but at the greater welfare cost of creating excess capacity. Entry incentives are also distorted. In low states, entrants obtain a share of revenue without increasing consumption, giving rise to a version of the common pool problem. In high states, firms do not appropriate the consumer surplus gained from marginal reductions in rationing. As a result of these o¤setting externalities, the number of firms may be excessive or insufficient. Inefficiency arises whether or not the rationing rule is efficient