A Question of Trust: Assessing the Fulfillment of Commitments in Terms of Strategies.

We aim at an adequate formal description of the dynamics of commitments and trust by transferring insights about actual human practices to a formal setting. Our framework is based on Belnap's theory of agents and choices in branching time (stit theory) and his analysis of commitments in terms of strategies. The main points are that (i) commitments come in various degrees of stringency, (ii) we can define a stringency ordering on an agent's possible strategies, and that (iii) trustworthiness can be spelled out in terms of strategies: An agent is living up to a given commitment, and thus, is trustworthy with respect to that commitment, if her strategy is at least as stringent as required. Overall trustworthiness of an agent can be defined by averaging over such single case assessments. [ABSTRACT FROM AUTHOR]