Revisiting the Roles of “Text” in Text Games

Yi Gu, Shunyu Yao, Chuang Gan, Josh Tenenbaum, Mo Yu


Abstract
Text games present opportunities for natural language understanding (NLU) methods to tackle reinforcement learning (RL) challenges. However, recent work has questioned the necessity of NLU by showing random text hashes could perform decently. In this paper, we pursue a fine-grained investigation into the roles of text in the face of different RL challenges, and reconcile that semantic and non-semantic language representations could be complementary rather than contrasting. Concretely, we propose a simple scheme to extract relevant contextual information into an approximate state hash as extra input for an RNN-based text agent. Such a lightweight plug-in achieves competitive performance with state-of-the-art text agents using advanced NLU techniques such as knowledge graph and passage retrieval, suggesting non-NLU methods might suffice to tackle the challenge of partial observability. However, if we remove RNN encoders and use approximate or even ground-truth state hash alone, the model performs miserably, which confirms the importance of semantic function approximation to tackle the challenge of combinatorially large observation and action spaces. Our findings and analysis provide new insights for designing better text game task setups and agents.
Anthology ID:
2022.findings-emnlp.510
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2022
Month:
December
Year:
2022
Address:
Abu Dhabi, United Arab Emirates
Editors:
Yoav Goldberg, Zornitsa Kozareva, Yue Zhang
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
6867–6876
Language:
URL:
https://aclanthology.org/2022.findings-emnlp.510
DOI:
10.18653/v1/2022.findings-emnlp.510
Bibkey:
Cite (ACL):
Yi Gu, Shunyu Yao, Chuang Gan, Josh Tenenbaum, and Mo Yu. 2022. Revisiting the Roles of “Text” in Text Games. In Findings of the Association for Computational Linguistics: EMNLP 2022, pages 6867–6876, Abu Dhabi, United Arab Emirates. Association for Computational Linguistics.
Cite (Informal):
Revisiting the Roles of “Text” in Text Games (Gu et al., Findings 2022)
Copy Citation:
PDF:
https://aclanthology.org/2022.findings-emnlp.510.pdf