Norman F. Carver, Victor R. Lesser, Daniel L. McCue
A plan recognition architecture is presented which exploits application-specific heuristic knowledge to quickly focus the search to a small set of plausible plan interpretations from the very large set of possible interpretations. The heuristic knowledge is formalized for use in a truth maintenance system where interpretation assumptions and their heuristic justifications are recorded. By formalizing this knowledge, the system is able to reason about the assumptions behind the current state of the interpretations. This makes intelligent backtracking and error detection possible.