HIERARCHICAL BELIEF STATES FOR DIGITAL ASSISTANTS

摘要

Systems and processes are disclosed for operating a digital assistant using a hierarchical belief state. In an exemplary process, a user utterance of a conversation is received. The state of belief about the conversation is determined. The belief state includes a plurality of dialog slots. Each dialogue slot of the plurality of dialogue slots includes a respective marginal certainty of a concept or attribute represented by each dialogue slot. A first dialogue slot of the plurality of dialogue slots further includes one or more coupling certainties for one or more interpretations arising from the first dialogue slot. A policy action is selected from the plurality of candidate policy actions corresponding to the belief state based on an ambient certainty of each dialogue slot of the plurality of dialogue slots and one or more combined certainties of the first dialogue slot. The selected policy action is performed.