Optimal pricing by a monopoly airline that faces capacity constraints during the peak demand period is studied. The existence of capacity constraints means that in order to expand output the airline must divert demand from the peak period to the off-peak period. A particular advance-purchase discount policy is shown to be the profit-maximizing method of selling tickets. If the advance-purchase requirement were infeasible, output and total surplus would both be lower.

We develop a methodology for analyzing the revenue and efficiency performance of auctions when buyers have private information about their willingness to pay and ability to pay. We then apply the framework to scenarios involving standard auction mechanisms. In the simplest case, where bidders face absolute spending limits, first-price auctions yield higher expected revenue and social surplus than second-price auctions. The revenue dominance of first-price auctions over second-price auctions carries over to the case where bidders have access to credit. These rankings are explained by differences in the extent to which financial constraints bind in different auction formats.

Procurement of an innovation often requires substantial effort by potential suppliers. Motivating effort may be difficult if the level of effort and quality of the resulting innovation are unverifiable, if innovators cannot benefit directly by marketing their innovations, and if the buyer cannot extract up-front payments from suppliers. We study the use of contests to procure an innovation in such an environment. An auction in which two suppliers are invited to innovate and then bid their prizes is optimal in a large class of contests. If contestants are asymmetric, it is optimal to handicap the most efficient one.

The ability of capital markets to distinguish firms of different value by the size of their initial equity offerings is attenuated when insiders can sell equity more than once. A model is developed in which there is price risk from holding equity between periods. When the uncertainty is small, there must be pooling in the first period. When uncertainty is large, the pooling equilibria dominate the separating equilibrium.

The ability of capital markets to distinguish firms of different value by the size of their initial equity offerings is attenuated when insiders can sell equity more than once. A model is developed in which there is price risk from holding equity between periods. When the uncertainty is small, there must be pooling in the first period. When uncertainty is large, the pooling equilibria dominate the separating equilibrium.

Yeon-Koo Che and Ian Gale (1998) studied the impact of imposing a cap on lobbying expenditures. They showed that a cap may lead to (1) greater expected aggregate expenditures and (2) a less efficient allocation of a political prize. In their comment, Todd Kaplan and David Wettstein (2005) show that if the cap is not rigid (i.e., its effect on the cost of lobbying is continuous) it has no effect.