Instrumental Variables (IV) methods identify internally valid causal effects for individuals whose treatment status is manipulable by the instrument at hand. Inference for other populations inevitably requires some sort of homogeneity assumption. I develop a simple theoretical framework that...

Received literature have shown that if competing networks are restricted to linear and uniform pricing, high access charges can facilitate collusion; a result that breaks down if we allow for non-linear and discriminatory pricing, however. We show that by adding unbalanced calling pattern to the...

This paper first inverts a general class of matrices for solving Bertrand equilibria from arbitrary coalition structures in linear Bertand oligopolies. It then studies merger incentives and obtains two main results; 1) for any asymmetric costs, mergers of any size are profitable; 2) a merger will...

We introduce capacity constrained competition between market-making intermediaries in a model in which agents can choose between trading with intermediaries, joining a search market or remaining inactive. Recently, market-making by a monopolistic intermediary has been analyzed by Rust and Hall...

There are a lot of goods which have network externalities. While the number of players who have such a good is small, they may not get enough utility from the goods. That is, players have an incentive to delay their decision, when they purchase the goods with network externalities. Delay causes...

This paper develops a monopolistic competition model to study the characteristics of products, such as quality improvement and product diversity (function-specialization and individualization), and the division of labor in production. Different from the ordinary economic model, our utility...

Cournot oligopoly has been studied almost exclusively under the implicit assumption of perfectly competitive factor markets. However,oligopolistic firms procure often factors of production from imperfectly competitive markets. Okuguchi(1998,2000) has analyzed Cournot oligopoly under the...

The analysis of economies of specialization at the individual level by Yang & Shi (1992) and Yang & Ng (1993) is combined with the Dixit & Stiglitz (1977) analysis of monopolistic-competitive firms to show that, ignoring administrative costs and indirect effects (such as rent-seeking), even if...

We derive a measure of firm speed of price adjustment that is directly inversely related to market power and compare this to the measure derived by Martin (1993). However, both measures are incorrect when firms have price conjectural variations. This is because Taylor expansions of the demand...

This paper uses household-level data of cellular usage to provide estimates of the implied switching costs that preclude consumers from switching providers in the face of competing offers. Our estimation differs from previous switching costs studies in that we are able to observe individual...