A Test of Performance Similarity Among Strategic Group Members in Conforming and Non‐conforming Industry Structures

Empirical tests have produced mixed support for a membership‐performance link in strategic groups, perhaps due to incomplete treatment of industry forces. We argue that strategic group concept is more useful for explaining performance differences among firms in some industries (where conditions favour conformity in firm conduct) than others. Using three industry structure constructs as criteria, 47 four‐digit SIC industries are classified into ‘conforming’ or ‘non‐conforming’ industry samples. Firms are then clustered into strategic groups in a separate treatment for each sample. Performance differences among groups are tested under conforming and non‐conforming industry conditions. Tests confirm membership effects on ROA and ROE are significantly stronger in ‘conforming’ industries, where stronger regression relationships between conduct variables and performance also obtain.