Defining electricity markets: an arbitrage cost approach

Market definition is a crucial component of antitrust policy. There is, however, no universally accepted method of carrying out market definition. While several approaches have been presented in the literature, each has its share of drawbacks. This paper suggests that a modeling technique based upon the theory of arbitrage is well suited to answering this question. After the empirical approach is presented, it is used to calculate antitrust market definitions between electricity hubs in the American West.