We study the percentage of welfare losses (PWL) yielded by imperfect competition under product differentiation. When demand is linear, if prices, outputs, costs and the number of firms can be observed, PWL is arbitrary in both Cournot and Bertrand equilibria. If in addition, the elasticity of...

In this paper we argue that two important causes of welfare losses in oligopolistic markets have been neglected. We show that in models where location is endogenous, welfare losses arising from wrong locations or from lack of market coverage may be substantial despite firms competing in prices....