TSUNAMI - SIMULTANEOUS UNDERSTANDING, ANSWERING, AND MEMORY INTERACTION FOR QUESTIONS

Question processing involves parsing, memory retrieval, question categ orization, initiation of appropriate answer-retrieval heuristics, answ er formulation, and output. Computational and psychological models hav e traditionally treated these processes as separate, sequential, indep endent, and in pursuit of a single answer type at a time. Here this vi ew is challenged and the implications of a theory in which question pr ocesses operate simultaneously on multiple question interpretations ar e explored. A highly interactive model is described in which an expect ation-driven parser generates multiple question candidates, including partially-specified candidates. Question candidates act as constraints for a matcher which activates memory items. An answer retrieval proce ss examines question candidates and the active portions of memory in a n attempt to generate answer candidates. Answer candidates are examine d by an output process that derives the final answer. These processes run simultaneously and interact. Three experiments on human question a nswering are also described which provide evidence that working memory load during question reading is affected by processes related to answ er retrieval.