Recent regulatory and technological changes have spurred the development of automated trading systems known as ECNs, or electronic communications networks. Proponents of the networks contend that ECNs can cut transaction costs, accelerate trade execution, and expand the price information...

The delivery and payment of bills over the Internet could offer many advantages—low processing costs and enhanced marketing opportunities for billers, savings in time and postage for customers. Nevertheless, electronic billing has not found favor with potential users. A lack of coordination...

The idea that an industry with sunk costs may be contestable even in the absence of long-term contracts has received little attention from formal economic theory yet is popular among monopolists facing antitrust suits. The paper formally illustrates the argument. In an infinitely repeated game,...