Abstract
In the 80s and 90s of the last century, in subdisciplines such as planning, text generation, and dialog systems, there was considerable interest in modeling the cognitive states of interacting autonomous agents. Theories such as Speech Act Theory (Austin 1962), the belief-desire-intentions model of Bratman (1987), and RST (Mann and Thompson 1988) together provide a framework in which to link cognitive state with language use. However, in general natural language understanding, little use was made of such theories, presumably because of the difficulty of some underlying tasks (such as syntactic parsing). In this talk, I propose that it is time to again think about the explicit modeling of cognitive state for participants in discourse, including in an understanding perspective. The perspective of cognitive state can provide a context in which many disparate NLP tasks can be classified and related. I will present three projects at Columbia which relate to the modeling of cognitive state:Discourse participants need to model each other’s cognitive states, and language makes this possible by providing special morphological, syntactic, and lexical markers. I present results in automatically determining the degree of belief of a speaker in the propositions in his or her utterance.In dialog (including written dialog), people pursue communicative intentions and usually cooperate on achieving them. Lack of cooperation can be a sign of lack of solidarity, and an assertion of power. I discuss some preliminary research on identifying dialog acts, communicative intention, and cooperative behavior in dialog.A social network is actually a perception on the part of people of how they relate to other people (rather than merely a collection of friends lists on a social networking site), and thus also a component of cognitive state. I report on initial work in extracting a social network from text.