Part IV Measurement, 15 Statistical Evidence
This chapter discusses the econometric approach, and its forensic use and misuse. Econometrics is a set of statistical techniques which estimate the overall and individual effects of variables that affects a variable of interest whether it be prices, output, and so on. The major attraction of multiple regression analysis is its ability to simultaneously account for, estimate, and quantify the myriad factors which influence prices or output. Specifically, in the context of cartel damage, it holds out the possibility of estimating the ‘but for’ price adjusted for the non-cartel factors which affect prices in a systematic and credible way. There are three general multiple regression approaches to estimating overcharges: dummy variable (DVA), predictive, and difference-in-differences. Other statistical techniques can be useful in damages cases such as time series analysis and event studies.