The Learning Curve in a Competitive Industry
研究自由进入和退出、价格接受型企业的行业中的学习曲线，发现存在唯一均衡，成熟企业获得学习租金，但某些条件下企业可能因成本或需求变化而退出，且市场结果总是社会有效的。
We consider the learning curve in an industry with free entry and exit, and price-taking firms. A unique equilibrium exists if the fixed cost is positive. While equilibrium profits are zero, mature firms earn rents on their learning, and, if costs are convex, no firm can profitably enter after the date the industry begins. Under some cost and demand conditions, however, firms may have to exit the market despite their experience gained earlier. Furthermore identical firms facing the same prices may produce different quantities. The market outcome is always socially efficient, even if dictates that firms exit after learning. Finally, actual and optimal industry concentration does not always increase in the intensity of learning.