Dialogue state tracking (DST) is a key component of taskoriented dialogue systems. DST estimates the user's goal at each user turn given the interaction until then. State of the art approaches for state tracking rely on deep learning methods, and represent dialogue state as a distribution over all possible slot values for each slot present in the ontology. Such a representation is not scalable when the set of possible values are unbounded (e.g., date, time or location) or dynamic (e.g., movies or usernames). Furthermore, training of such models requires labeled data, where each user turn is annotated with the dialogue state, which makes building models for new domains challenging. In this paper, we present a scalable multi-domain deep learning based approach for DST. We introduce a novel framework for state tracking which is independent of the slot value set, and represent the dialogue state as a distribution over a set of values of interest (candidate set) derived from the dialogue history or knowledge. Restricting these candidate sets to be bounded in size addresses the problem of slot-scalability. Furthermore, by leveraging the slotindependent architecture and transfer learning, we show that our proposed approach facilitates quick adaptation to new domains.
Semi-scalable Belief Tracker REF proposed an approach that can generate fixed-length candidate sets for each of the slots from the dialogue history.
Scalable multi-domain dialogue state tracking
2017 IEEE Automatic Speech Recognition and Understanding Workshop (ASRU)
2017 IEEE Automatic Speech Recognition and Understanding Workshop (ASRU)
Computer Science