CR-Walker: Tree-Structured Graph Reasoning and Dialog Acts for Conversational Recommendation

Wenchang Ma, Ryuichi Takanobu, Minlie Huang


Abstract
Growing interests have been attracted in Conversational Recommender Systems (CRS), which explore user preference through conversational interactions in order to make appropriate recommendation. However, there is still a lack of ability in existing CRS to (1) traverse multiple reasoning paths over background knowledge to introduce relevant items and attributes, and (2) arrange selected entities appropriately under current system intents to control response generation. To address these issues, we propose CR-Walker in this paper, a model that performs tree-structured reasoning on a knowledge graph, and generates informative dialog acts to guide language generation. The unique scheme of tree-structured reasoning views the traversed entity at each hop as part of dialog acts to facilitate language generation, which links how entities are selected and expressed. Automatic and human evaluations show that CR-Walker can arrive at more accurate recommendation, and generate more informative and engaging responses.
Anthology ID:
2021.emnlp-main.139
Volume:
Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2021
Address:
Online and Punta Cana, Dominican Republic
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1839–1851
Language:
URL:
https://aclanthology.org/2021.emnlp-main.139
DOI:
10.18653/v1/2021.emnlp-main.139
Bibkey:
Cite (ACL):
Wenchang Ma, Ryuichi Takanobu, and Minlie Huang. 2021. CR-Walker: Tree-Structured Graph Reasoning and Dialog Acts for Conversational Recommendation. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 1839–1851, Online and Punta Cana, Dominican Republic. Association for Computational Linguistics.
Cite (Informal):
CR-Walker: Tree-Structured Graph Reasoning and Dialog Acts for Conversational Recommendation (Ma et al., EMNLP 2021)
Copy Citation:
PDF:
https://aclanthology.org/2021.emnlp-main.139.pdf
Video:
 https://aclanthology.org/2021.emnlp-main.139.mp4
Code
 truthless11/CR-Walker
Data
ConceptNetReDial