Known-Item Searches Resulting in Zero Hits: Considerations for Discovery Systems

Behnert, C., & Lewandowski, D. (2017). Known-item Searches Resulting in Zero Hits: Considerations for Discovery Systems. The Journal of Academic Librarianship, 43(2), 128–134.

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The goal of this article is to understand the reasons why known-item search queries entered in a discovery system return zero hits. We analyze a sample of 708 known-item queries and classify them into four categories of zero hits with regard to whether the item is held by the library and whether the query is formulated correctly: (1) Item in stock, but query incorrect, (2) Item not in stock, (3) Item in stock, but incomplete or erroneous metadata, (4) Query is ambiguous or not understandable. The main reasons for zero hits are caused by acquisition and erroneous search queries. We discuss possible solutions for known-item queries resulting in zero hits from the side of the system and show that 30% of zero hits could easily be avoided by applying automatic spelling correction. We argue that libraries can improve their discovery systems or online catalogs by applying strategies to avoid or cope with zero hits inspired by web search engines and commercial search web sites.