Contingent charges for financial services, such as fees for unauthorized overdrafts, are often controversial. We study the economics of contingent charges in a stylized setting with naive and sophisticated consumers. We contrast situations where the naive benefit from the presence of sophisticated consumers with situations where competition works to subsidize the sophisticated at the expense of the naive, arguably unfairly. The case for regulatory intervention in these situations depends in good part, but not only, on the weight placed on distributional concerns. The economic and legal issues at stake are well illustrated by a case on bank charges recently decided by the U.K. Supreme Court.

We examine competitive non-linear pricing in a model in which consumers have heterogeneous and elastic demands and can buy from more than one supplier. It is an equilibrium for firms to offer a menu of efficient two-part tariffs, where the discount for one-stop shopping is such that the elasticity of “demand for two-stop shopping” equals two. Compared with linear pricing, non-linear pricing tends to raise profit but harm consumers when: (i) demand is elastic, (ii) there is heterogeneity in consumer demand, (iii) consumers incur shopping costs when buying from more than one firm, and (iv) a consumer's brand preference for one product is correlated with her brand preference for another product. Non-linear pricing is more likely to lead to welfare gains when (iii) and (iv) hold, but (ii) does not.

We explore patterns of price competition in an oligopoly where consumers vary in the set of firms they consider for their purchase and buy from the lowest‐priced firm they consider. We study a pattern of consideration, termed “symmetric interactions,” that generalizes models used in existing work (duopoly, symmetric firms, and firms with independent reach). Within this class, equilibrium profits are proportional to a firm's reach, firms with a larger reach set higher average prices, and a reduction in the number of firms (either by exit or by merger) harms consumers. However, increased competition (either by entry or by increased consumer awareness) does not always benefit consumers. We go on to study patterns of consideration with asymmetric interactions. In situations with disjoint reach and with nested reach, we find equilibria in which price competition is “duopolistic”: only two firms compete within each price range. We characterize the contrasting equilibrium patterns of price competition for all patterns of consideration in the three‐firm case.

We present a model in which a principal delegates the choice of project to an agent with different preferences. The principal determines the set of projects from which the agent may choose. The principal can verify the characteristics of the project chosen by the agent, but does not know which other projects were available to the agent. We consider situations where the collection of available projects is exogenous to the agent but uncertain, where the agent must invest effort to discover a project, where the principal can pay the agent to choose a desirable project, and where the principal can adopt more complex schemes than simple permission sets.

Edgeworth’s paradox of taxation occurs when an increase in the unit cost of a product causes a multiproduct monopolist to reduce prices. We give simple illustrations of the paradox and a general analysis of the case of linear marginal cost and demand conditions, and we characterize which matrices of cost pass-through terms are consistent with profit maximization. When the firm supplies at least one pair of substitute products, we show how Edgeworth’s paradox always occurs with a suitable choice of cost function. We then establish a connection between Ramsey pricing and the paradox in a form relating to consumer surplus.

Is more intense product market competition and imitation good or bad for growth? This question is addressed in the context of an endogenous growth model with “step-by-step” innovations, in which technological laggards must first catch up with the leading-edge technology before battling for technological leadership in the future. In contrast to earlier Schumpeterian models in which innovations are always made by outsider firms who earn no rents if they fail to innovate and become monopolies if they do innovate, here we find: first, that the usual Schumpeterian effect of more intense product market competition (PMC) is almost always outweighed by the increased incentive for firms to innovate in order to escape competition, so that PMC has a positive effect on growth; second, that a little imitation is almost always growth-enhancing, as it promotes more frequent neck-and-neck competition, but too much imitation is unambiguously growth-reducing. The model thus points to complementary roles for competition (anti-trust) policy and patent policy.

This paper presents a general analysis of the effects of monopolistic third-degree price discrimination on welfare and output when all markets are served. Sufficient conditions—involving straightforward comparisons of the curvatures of the direct and inverse demand functions in the different markets—are presented for discrimination to have negative or positive effects on social welfare and output.