Robust Trust Management (Doctoral Consortium)

To explain, in multi-agent based e-marketplaces, self-interested selling agents may act maliciously by not delivering products with the same quality as promised. It is thus important for buying agents to analyze their quality and determine which sellers to do business with, based on their previous experience with the sellers. However, realistically, in most e-marketplaces, buyers often encounter sellers with which they have no previous experience. In such cases, they can query other buyers (called advisors) about the sellers. But, advisors may act dishonestly by providing misleading opinions (unfair ratings) to promote low quality sellers or demote sellers with high quality. Hence, it is necessary to evaluate the quality of advisors’ opinions to determine their reliability. While it is prima facie necessary to gather opinions about a seller, a buyer may not need to query all the advisors about the seller, since the cost of querying all the advisors may be greater than the value derived from a successful transaction with the seller. Thereby, it is necessary to design an optimal scheme to selectively query advisors and choose a quality seller to perform transaction, in order to maximize the utility of the buyer in the long run.