• I. The empirical model
  • II. Data sample and profit definitions
  • III. Empirical results
  • A. Specification test
  • B. Test of log structure
  • C. Regression results of the empirical model
  • IV. Firm-specific versus industry-specific effects explaining firm profit differences
  • A. Results on the firm versus singel-industry effects analysis
  • B. Results on the firm versus multiple industry effects analysis
  • V. Explanation of permanent profit levels by firm-specific factors
  • VI. Concluding remarks