Collaborative Plans for Group Activities

The original formulation of SharedPlans [Grosz and Sidner, 1990] was developed to provide a model of collaborative planning in which it was not necessary for one agent to have intentions toward an act of a different agent. This formulation provided for two agents to coordinate their activities without introducing any notion of jointly held intentions (or, 'weintentions'). However, it only treated activities that directly decomposed into single agents actions. In this paper we provide a revised and expanded version of SharedPlans that accommodates actions involving groups of agents as well as complex actions that decompose into multi-agent actions. The new definitions also allow for contracting out certain actions, and provide a model with the features required in Bratman's account of shared cooperative activity [Bratman, 1992]. A reformulation of the model of individual plans that meshes with the definition of SharedPlans is also provided.