Does Selective Search Benefit from WAND Optimization?

Abstract

Selective search is a distributed retrieval technique that reduces the computational cost of large-scale information retrieval. By partitioning the collection into topical shards, and using a resource selection algorithm to identify a subset of shards to search, selective search allows retrieval effectiveness to be maintained while evaluating fewer postings, often resulting in 90+% reductions in querying cost. However, there has been only limited attention given to the interaction between dynamic pruning algorithms and topical index shards. We demonstrate that the WAND dynamic pruning algorithm is more effective on topical index shards than it is on randomly-organized index shards, and that ..