Economies of Scale and Barriers to Entry
Dixit模型表明，在位企业通过选择产能阻止进入，但无法实施非理性威胁；在线性或凹需求下，最小有效规模企业的资本成本限制了可屏蔽的垄断利润现值，暗示规模经济构成的进入壁垒通常不重要。
Dixit has recently presented a model in which established firms select capacity to discourage entry but cannot employ threats they would not rationally execute after entry. Entry deterrence in a slight modification of this model involves the classical limit-price output. Under linear or concave demand, however, the capital cost of a firm of minimum efficient scale is an upper bound on the present value of the monopoly profit stream that can be shielded from entry. It is argued that this suggests the general unimportance of entry barriers erected by scale economies.