We consider an information design problem when the sender faces ambiguity regarding the probability distribution over the states of the world, the utility function and the prior of the receiver. The solution concept is minimax loss (regret), that is, the sender minimizes the distance from the...

Trust and trust management represent the very foundations of Computer and Network Security Protocols enabling all cyber activities. The recent spate of national and global high-impact cyber security compromises threats, vulnerabilities and exposures leads to fundamental questioning of trust as...

Network externality is a prominent feature of increasingly many products: the marginal payoff of one's consumption increases as his neighbors consume more. In- formation of network structure is important to the seller, but is often privately known to the buyers. We model a monopoly's optimal...

We model a competitive labor market with heterogeneous firms of varying productivities, and consider two information-collection processes: searching for "good news" about applicants, and searching for "bad news." Under the former, firms seek positive signals to qualify applicants, and under the...

Consider a two-product firm that decides on the quality of each product. Product quality is unknown to consumers. If the firm sells both products under the same brand name, consumers adjust their beliefs about quality subject to the performance of both products. We show that if the probability...

In a market environment with random detection of product quality, a firm can employ umbrella branding as a strategy to convince consumers of the high quality of its products. Alternatively, a firm can rely on external certification of the quality of one or both of its products. We characterize...

Consider a two-product firm that decides on the quality of each product. Product quality is unknown to consumers. If the firm sells both products under the same brand name, consumers adjust their beliefs about quality subject to the performance of both products. We show that if the probability...

This paper investigates the possibility that wealth (holdings of money) serves as a signal of ability to produce high quality products for agents who cannot directly observe the quality of the products. A producer’s wealth may advertise past success in selling products to agents who knew the...

We develop a model of consulting (advising) where the role of the consultant is that she can reveal signals to her client which refine the client’s original private estimate of the profitability of a project. Importantly, only the client can observe or evaluate these signals, the consultant...

We study a communication game of common interest in which the sender observes one of infinite types and sends one of finite messages which is interpreted by the receiver. In equilibrium there is no full separation but types are clustered into convex categories. We give a full characterization of...