Differences in prices paid by putative class members (quot;price dispersionquot;) often become a focal point for class certification in antitrust matters. This paper discusses how an economic analysis of the existence, extent, and nature of price dispersion faced by plaintiffs seeking class...

In regressions using a semi-logarithmic functional form that include a dummy variable, Kennedy (1981) showed that instead of interpreting the dummy coefficient directly, one needs to “correct” it to estimate the percentage effect of the dummy variable on the dependent variable. In the...