This paper examines the evolution of a skew distribution of firm sizes from the viewpoint of the 'Bounds' approach to market structure. It confines attention to the role played by non-strategic factors (statistical independence, and cost sideeffects). A model is proposed, which leads to a...

This paper examines the frequency, pervasiveness, and determinants of product switching by US manufacturing firms. We find that one-half of firms alter their mix of five-digit SIC products every five years, that product switching is correlated with both firm- and firm-product attributes, and...

This paper proposes an equilibrium concept for a class of games in which players make irreversible costly decisions; these games have been widely used in the recent I.O. literature. The equilibrium concept is defined, not in the space of strategies, but in the space of (observable) outcomes. It...

This paper uses a difference-in-difference estimator to test whether the introduction of patient choice and hospital competition in the English NHS in January 2006 has prompted hospitals to become more efficient. Efficiency was measured using hospitals’ average length of stay (LOS) for...

This paper reviews the recent literature on game-theoretic models of market structure and their empirical implementation.