In a typical bank credit card transaction, the merchant's bank pays an interchange fee, collectively determined by all participating banks, to the cardholder's bank. This paper shows how the interchange fee balances charges between cardholders and merchants under imperfect competition. The...

To inform debates about deregulation of wholesale markets for electricity, we estimate effective concentration in those markets in the contiguous United States in 1978. Our estimates are based on simulated oligopolistic equilibria, the characteristics of which are derived from a new and...