Dialogue Act Sequence Labeling Using Hierarchical Encoder With CRF

Authors

  • Harshit Kumar IBM Research
  • Arvind Agarwal IBM Research
  • Riddhiman Dasgupta IBM Research
  • Sachindra Joshi IBM Research

Keywords:

CRF, LSTM, dialog act sequence labeling

Abstract

Dialogue Act recognition associate dialogue acts (i.e., semantic labels) to utterances in a conversation. The problem of associating semantic labels to utterances can be treated as a sequence labeling problem. In this work, we build a hierarchical recurrent neural network using bidirectional LSTM as a base unit and the conditional random field (CRF) as the top layer to classify each utterance into its corresponding dialogue act. The hierarchical network learns representations at multiple levels, i.e., word level, utterance level, and conversation level. The conversation level representations are input to the CRF layer, which takes into account not only all previous utterances but also their dialogue acts, thus modeling the dependency among both, labels and utterances, an important consideration of natural dialogue. We validate our approach on two different benchmark data sets, Switchboard and Meeting Recorder Dialogue Act, and show performance improvement over the state-of-the-art methods by 2.2% and 4.1% absolute points, respectively. It is worth noting that the inter-annotator agreement on Switchboard data set is 84%, and our method is able to achieve the accuracy of about 79% despite being trained on the noisy data.

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Published

2018-04-29

How to Cite

Kumar, H., Agarwal, A., Dasgupta, R., & Joshi, S. (2018). Dialogue Act Sequence Labeling Using Hierarchical Encoder With CRF. Proceedings of the AAAI Conference on Artificial Intelligence, 32(1). Retrieved from https://ojs.aaai.org/index.php/AAAI/article/view/11701