Long Waves and Short Waves: Growth Through Intensive and Extensive Search
内生化重大发现的频率及其改进程度，通过四个公理导出指导探索努力的信念，权衡重大新发现与成功改进旧发现的机会，并推导发明活动的时间序列性质。
This paper endogenizes the frequency of major discoveries and the extent of their refinement. Four axioms deliver a one-parameter family of beliefs that guide exploratory effort. Such effort trades off the prospect of major new discovery against the chance of successfully refining discoveries made in the past. The only other parameter is the cost of making new discoveries relative to the cost of refining old ones. The paper derives time-series properties of inventive activity as they relate to the two parameters, and it discusses several specific inventions and their subsequent refinement. Copyright 1990 by The Econometric Society.