Search patent of the week: Stochastic Retrieval Reranking: Precision Over Recall in Search
The new Podcats episode examines a Google research paper that describes how search engines can improve their ranking results by optimizing retrieval and reranking together, rather than relying primarily on high recall scores in the first phase. It argues that precision in retrieval is more important for optimal ranking and proposes a new theoretical framework called ECR. The paper also presents methods for adapting ECR for multi-stage ranking systems and discusses approaches for estimating query-specific abandonment thresholds for retrieval, highlighting WIG as a useful metric. Finally, the different optimization of retrieval for commercial versus informational search queries is highlighted.