对多阶段检索管道中的BERT Rerankers进行重新思考培训
预先训练的深度语言模型(LM)改进了文本检索的最新技术。从深层LM进行微调的重排程序基于丰富的上下文匹配信号来估计候选者相关性。..
Rethink Training of BERT Rerankers in Multi-Stage Retrieval Pipeline
Pre-trained deep language models~(LM) have advanced the state-of-the-art of text retrieval. Rerankers fine-tuned from deep LM estimates candidate relevance based on rich contextualized matching signals.Meanwhile, deep LMs can also be leveraged to improve search index, building retrievers with better recall. One would expect a straightforward combination of both in a pipeline to have additive performance gain. In this paper, we discover otherwise and that popular reranker cannot fully exploit the improved retrieval result. We, therefore, propose a Localized Contrastive Estimation (LCE) for training rerankers and demonstrate it significantly improves deep two-stage models.