Corporate and industry effects on business unit competitive position
将市场份额作为竞争地位的代理变量，分解其方差为公司、行业和业务单元三个层面，发现公司效应在更窄行业定义、包含小业务单元和中型企业时显著大于零，且各效应相对重要性取决于样本构建标准。
We partition the variances of market shares, which we use as surrogates for competitive position, of the business units of all public manufacturing companies available in the Trinet data base into industry factors, corporate parent-specific factors, and business unit-specific factors. Our results differ somewhat from Rumelt's (1991), which decomposed variances in profitability. We find that corporate parent effects on market share are considerably greater than zero when lines of business are defined more narrowly, when small business units are included, and when firms are medium-sized. Our results suggest that the relative importance of corporate, industry, and business unit effects depends on the types of criteria, such as the level of industry aggregation, whether small business units are included, and firm size, that are used to construct samples. Copyright © 2000 John Wiley & Sons, Ltd.