The Persistence of Shocks to Profitability
基于1981-1994年美国公司数据，研究发现行业对盈利能力的增量效应比公司主体和具体业务更持久，行业结构变化的影响比企业结构变化更持久。
In this study, we use data for 1981 through 1994 on a large sample of U.S. companies to examine the persistence of incremental industry, corporate-parent, and business-specific effects on profitability. Our results indicate that the incremental effects of industry on profitability persist longer than the incremental effects of the corporate parent and of the specific business. Changes in industry structure have a more persistent impact on profitability than do changes in firm structure. © 1999 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology