Price Dispersion in the Lab and on the Internet: Theory and Evidence

Price dispersion is ubiquitous in settings that closely approximate textbook Bertrand competition. We show (Propositions 2 and 3) that only a little bounded rationality among sellers is needed to rationalize such dispersion. A variety of statistical tests, based on data sets from two independent laboratory experiments and structural estimates of the parameters of our models, suggest that bounded rationality based theories of price dispersion organize the data remarkably well. Evidence is also presented which suggests that the models are consistent with data from a leading Internet price comparison site.