The Panzar-Rosse test has been widely applied to assess competitive conduct, often in specifications controlling for firm scale or using a price equation. We show that neither a price equation nor a scaled revenue function yields a valid measure for competitive conduct. Moreover, even an unscaled revenue function generally requires additional information about costs and market equilibrium to infer the degree of competition. Our theoretical findings are confirmed by an empirical analysis of competition in banking, using a sample containing more than 100,000 bank-year observations on more than 17,000 banks in 63 countries during the years 1994 to 2004.

The quiet life hypothesis posits that firms with market power incur inefficiencies rather than reap monopolistic rents. We propose a simple adjustment to Lerner indices to account for the possibility of forgone rents to test this hypothesis. For a large sample of U.S. commercial banks, we find that adjusted Lerner indices are significantly larger than conventional Lerner indices and trending upward over time. Instrumental variable regressions reject the quiet life hypothesis for cost inefficiencies. However, Lerner indices adjusted for profit inefficiencies reveal a quiet life among U.S. banks.

Chung and Cox (1994) provided an intuitively appealing stochastic model indicating that superstars may exist regardless of talent, giving rise to the Yule distribution. We adopt a different empirical approach and test its goodness of fit using a parametric bootstrap and several powerful test statistics. Just like the discrete Pareto distribution, it is overwhelmingly rejected: it is a fairly accurate approximation of the lower quantiles of the superstar distribution but overestimates the snowball effect that makes consumers purchase records of the most successful artists. In other words, the Yule distribution captures stardom, but not superstardom. A generalization of the Yule distribution provides an excellent fit in two of the three data sets.