Beyond Two-Tower: Attribute Guided Representation Learning for Candidate Retrieval
Hongyu Shan, Qishen Zhang, Zhongyi Liu, Guannan Zhang, Chenliang Li · 2023
Candidate retrieval is a key part of the modern search engines whose goal is to find candidate items that are semantically related to the query from a large item pool. The core difference against the later ranking stage is the requirement of low latency. Hence, two-tower structure with two parallel yet independent encoder for both query and item is prevalent in many systems. In these efforts, the semantic information of a query and a candidate item is fed into the corresponding encoder and then use their representations for retrieval. With the popularity of pre-trained semantic models, the state-of-the-art for semantic retrieval tasks has achieved the significant performance gain.