The Life Cycle of a Competitive Industry
用竞争模型解释行业演化中企业数量先升后降的非单调现象，创新机会驱动进入、创新失败导致退出，并用美国汽车轮胎行业数据估计模型。
Firm numbers first rise, then later fall, as an industry evolves. This nonmonotonicity is explained using a competitive model in which innovation opportunities fuel entry and relative failure to innovate prompts exit; equilibrium time paths for price and quantity also share features of the data. The model is estimated using data from the U.S. automobile tire industry, a particularly dramatic example of the nonmonotonicity in firm numbers. Copyright 1994 by University of Chicago Press.