Person:

Grosz, Barbara

For individually motivated agents to work collaboratively to satisfy shared goals, they must make decisions about actions and intentions that take into account their commitments to group activities. This paper examines the role of social consciousness in the process of reconciling intentions to do group-related actions with other, conflicting intentions. We operationalize the notion of social consciousness and provide a first attempt to formally add social consciousness to a cooperative decision-making model. We define a measure of social consciousness; describe its incorporation into the SPIRE experimental system, a simulation environment that allows the process of intention reconciliation in team contexts to be studied; and present results of several experiments that investigate the interaction in decision-making of measures of group and individual good. In particular, we investigate the effect of varying levels of social consciousness on the utility of the group and the individuals it comprises. A key finding is that an intermediate level of social consciousness yields better results in certain circumstances than an extreme commitment. We suggest preliminary principles for designers of collaborative agents based on the results.

When rational, utility-maximizing agents encounter an opportunity to collaborate on a group activity they must determine whether to commit to that activity. We refer to this problem as the initial-commitment decision problem (ICDP). The paper describes a mechanism that agents may use to solve the ICDP. The mechanism is based on a combinatorial auction in which agents bid on sets of roles in the group activity, each role comprising constituent subtasks that must be done by the same agent. Each bid may specify constraints on the execution times of the subtasks it covers. This mechanism permits agents to keep most details of their individual schedules of prior commitments private. The paper reports the results of several experiments testing the performance of the mechanism. These results demonstrate a significant improvement in performance when constituent subtasks are grouped into roles. They also show that as the number of time constraints in bids increases, the probability that there is a solution decreases, the cost of an optimal solution (if one exists) increases, and the time required to find an optimal solution (if one exists) decreases. The paper also describes several strategies that agents might employ when using this mechanism.