Using expectation to enable spoken variable initiative dialog
Ronnie W. Smith, D. Richard Hipp · 1992
This paper discusses how dialog expectations may be ex- ploited in solving some important problems of dialog processing.Our model for expectation-driven dialog processing extends the theoretical model of attentional state by Grosz and Sidner as it provides a practical application of the model.In addition to a presentation of our model and a discussion of its application to dialog processing problems, the paper reports on results obtained from the use of our voice-interactive dialog system.The results are baaed on over 140 dialogs and over 2800 spoken user utterances. The Need for Contextual Dialog ProcessingAmong researchers in natural language processing it is common knowledge that contextual information must be used in order to properly understand and respond to utterances in a dialog (see Allen [5] for a general discussion).This is true for all types of dialogs including tack-oriented dialogs, the object of study in our research.Consider the following subdialog (C denotes the computer, and U the user.) (1) c: You need to measure the voltage between cormectora 24 and 83.(2) u: Uhere do I connect this red wire?(3) c: To connector 24.(4) u: Where is it?(5) c: To the right of the switch.(6) U: I have made the connection.In utterance(2) theuser refers to "this red wire" although no wire has been explicitly mentioned.Itcame into context when the discussion of meaeuring the voltage was introduced.This implicitly introduced the voltmeter into context along with its wires, one of which is this red wire.Sinrilarly, the "it" of utterance (4)refers to connector 24, which is mentioned in utterance (3).User utterances (2) and (4) cannot be understood in isolation.They can only be understood by using the contextual information available as the result of previous utterances in the dialog.