Changes of action ontology in conversation among collaborators using virtual space

Analyzer of conversation is effective to estimate a person´s intention and to predict the person´s actions, and such function of the analyzer can be utilized for watch-over system. It is, however, difficult to make such perfect analyzer with a simple computer system. Hence in this study, we focused on change in utilization of corpus by limiting the situation of human interaction. We investigated construction of common grounds and sharing ontology based on action words using utterances occurred in the skill acquisition of virtual collaborative conveyer task. Specifically, we constructed corpus and analyzed conversation between three adults that occurred while completing 10 task trials. We extracted action words from the conversation and classified them into three categories, Move, Stop, and Turn. Action words were defined as the word directly related to transportation task. The results were that the number of action word types decreased in all action word categories and in all experimental groups, showing that the ontology of action concepts converged into a few words in each category. The results also showed that the construction of common grounds among the participants seems to contribute to the convergence of action ontology.