Integrating Retrieval and Generation Tasks for Deep Semantic Matching in Xianyu Search
The paper introduces SimBert, a later‑fusion model that jointly trains a dual‑tower retrieval component and an auxiliary generation task on the item tower, using a two‑stage pre‑training and fine‑tuning pipeline, which yields a 3.6% relevance boost and reduces bad‑case rates in Xianyu search.