Getting Serious About Parsing Plans: A Grammatical Analysis of Plan Recognition

Abstract

This paper is concerned with making precise the notion that recognizing plans is much like parsing text. To this end, it establishes a correspondence between Kautz ’ plan recognition formalism and existing grammatical frameworks. This mapping helps isolate subsets of Kautz ’ formalism in which plan recognition can be efficiently performed by parsing. In recent years, plan recognition has emerged as one of the best-understood frameworks for analyzing goaldirected behavior. Interest in plan recognition has led to the development of diverse recognition strategies.l One approach suggested several times is that of parsing plan descriptions (Sidner (1985), Ross & Lewis (1987)). A plan is typically described as a sequence of steps, so interpreting some observations in terms of a plan can