Title
Ensemble-based deep reinforcement learning for chatbots.
Abstract
Trainable chatbots that exhibit fluent and human-like conversations remain a big challenge in artificial intelligence. Deep Reinforcement Learning (DRL) is promising for addressing this challenge, but its successful application remains an open question. This article describes a novel ensemble-based approach applied to value-based DRL chatbots, which use finite action sets as a form of meaning representation. In our approach, while dialogue actions are derived from sentence clustering, the training datasets in our ensemble are derived from dialogue clustering. The latter aim to induce specialised agents that learn to interact in a particular style. In order to facilitate neural chatbot training using our proposed approach, we assume dialogue data in raw text only – without any manually-labelled data. Experimental results using chitchat data reveal that (1) near human-like dialogue policies can be induced, (2) generalisation to unseen data is a difficult problem, and (3) training an ensemble of chatbot agents is essential for improved performance over using a single agent. In addition to evaluations using held-out data, our results are further supported by a human evaluation that rated dialogues in terms of fluency, engagingness and consistency – which revealed that our proposed dialogue rewards strongly correlate with human judgements.
Year
DOI
Venue
2019
10.1016/j.neucom.2019.08.007
Neurocomputing
Keywords
Field
DocType
Deep supervised/unsupervised/reinforcement learning,Neural chatbots
Generalization,Fluency,Sentence clustering,Artificial intelligence,Natural language processing,Chatbot,Cluster analysis,Machine learning,Mathematics,Reinforcement learning
Journal
Volume
ISSN
Citations 
366
0925-2312
0
PageRank 
References 
Authors
0.34
0
10
Name
Order
Citations
PageRank
Heriberto Cuayáhuitl124722.20
Donghyeon Lee268.27
Seonghan Ryu300.34
Yongjin Cho400.34
Sungja Choi500.34
Satish Reddy Indurthi600.34
Seunghak Yu700.68
Hyungtak Choi800.34
Inchul Hwang973.02
Jihie Kim1088491.69