The Devastating Effect Of Information Brokers In MAS
In many multi-agent systems we find information brokers Ė agents that can disambiguate noisy signals upon payment of a fee (e.g., Carfax that provides reports on car histories, credit report companies, experts that provide accurate estimates on auctioned items). In this talk I will show that better information can hurt: the presence of the expert, even if the use of her services is optional, can degrade both individual agentsí utilities and overall social welfare. The talk will focus on information brokers in two specific domains: auctions (where the provided information relates to the common value of the auctioned item) and distributed agent matching. For the first, Iíll show that with the existence of the information provider, in conflict with classic auction theory, the auctioneer will not necessarily find it beneficial to have more bidders participate in the auction and similarly bidders will not necessarily prefer less competition. Also, bidders' unawareness of the auctioneer's option to purchase the information does not necessarily play into the hands of the auctioneer and, similarly, bidders may sometimes benefit from not knowing that the auctioneer has the option to purchase such information. For the distributed matching application Iíll show that the externality imposed by the fact that others are consulting the expert can lead to a situation where the equilibrium outcome is that everyone consults the expert, even though all agents would be better off if the expert were not present. In both cases the agents may find it beneficial to pay the information-provider in order to leave the market (or alternatively publicly increase the price of the information she offers).
David Sarne is a senior lecturer in the Department of Computer Science at Bar-Ilan University. He is also the head of the Intelligent Information Agents (IIA) group. Before joining Bar-Ilan he was a Post-Doc at Harvard University for two years, following several years in the Israeli hi-tech industry. He holds a B.Sc. in Industrial Engineering and an M.Sc. in Information Systems (both from Tel-Aviv University) and a Ph.D. in Computer Science from Bar-Ilan University. His main research interest is in the role that information plays in complex, uncertain multi-agent sequential decision settings, encompassing various types of environments, distinguished by the agent's goals (fully-cooperative or self-interested) and design (fully rational or bounded rational).