Search engines enable advertisers to target consumers based on the query they have entered.  In a framework with horizontal product differentiation, imperfect product information and in which consumers incur search costs, I study a game in which advertisers have to choose a price and a set of...

The welfare and output effects of monopoly third-degree price discrimination are analyzed when inverse demand functions are parallel.  Welfare is higher with discrimination than with a uniform price when demand functions are derived from the logistic distribution, and from a more general class...

The welfare effects of third-degree price discrimination are known to be negative when demand functions are linear, marginal cost is constant and all markets are served. This paper shows that discrimination lowers welfare for a more general class of demand functions. Demand varies across markets...

The aim of this paper is to provide empirically testable predictions regarding the relationship between market size and concentration. In a model of endogenous horizontal mergers, it is shown that concentrated outcomes cannot be supported in a free entry equilibrium in large exogenous sunk cost...

Switching costs and network effects bind customers to vendors if products are incompatible, locking customers or even markets in to early choices. Lock-in hinders customers from changing suppliers in response to (predictable or unpredictable) changes in efficiency, and gives vendors lucrative ex...

This paper presents simple conditions for monopoly third-degree price discrimination to have negative or positive effects on aggregate consumer surplus.  Consumer surplus is often reduced by discrimination, for example when total welfare (consumer surplus and profits) falls.  Surplus increases...

The main section of the paper analyzes the principles and practice of competition policy for utilities under six headings: price discrimination and cross-subsidy; oligopolistic behaviour; mergers and takeovers; vertical structure; network access pricing; and historical entry barriers. The...

Sufficient conditions are developed for third-degree price discrimination by a monopolist serving all markets to reduce and raise social welfare.  Welfare falls if the demand function in the market whose price is higher with discrimination is at least as convex as that in the other market (at...

The welfare effects of third-degree price discrimination are analyzed when demand in one market is an additively shifted version of demand in the other market and both markets are served with uniform pricing. Social welfare is lower with discrimination if the slope of demand is log-concave or...

This paper uses convexity arguments to determine the effects of monopolistic third-degree price discrimination on total output and welfare. We focus on benchmark cases, including constant demand elasticities, with constant curvature of inverse demand σ. We show how the effects of price...