We consider auctions for a single indivisible object, in the case where the bidders have information about each other which is not available to the seller. We show that the seller can use this information to his own benefit, and we completely characterize the environments in which a well chosen auction gives him the same expected payoff as that obtainable were he able to sell the object with full information about each bidder's willingness to pay. We provide this characterization for auctions in which the bidders have dominant strategies, and for those where the relevant equilibrium concept is Bayesian Nash. In both setups , the existence of these auctions hinges on the possibility of constructing lotteries with the correct properties.

This paper deals with the optimal design of resource allocation mechanisms in the presence of asymmetric information. A buyer's valuation function is allowed to depend on the characteristics of other buyers as well as his own and sufficient conditions are provided under which the seller can extract the full surplus from the buyers in an "ex post Nash" equilibrium. The result is then applied to the important problem of optimal auction design.

We examine a general equilibrium model with asymmetrically informed agents. The presence of asymmetric information generally presents a conflict between incentive compatibility and Pareto efficiency. We present a notion of informational size and show that the conflict between incentive compatibility and efficiency can be made arbitrarily small if agents are of sufficiently small informational size.

We investigated the effect of time, temperature, and the presence of sodium chloride, nitrates, and nitrites in the medium on the growth and production of enterotoxin B by Staphylococcus aureus. Assays by the double gel-diffusion method showed that m enterotoxin B production occurs at the beginning of the stationary phase of growth. Lowering the tanperature of incubation decreased the amount of toxin produced without affecting the total amount of growth. Increases in concentration of curing salts reduced toxin production more rapidly than cell growth. The relationship of these observations to food-poisoning outbreaks is briefly discussed.