Comparative Recall and Precision of Simple and Expert Searches in Google Scholar and Eight Other Databases

This study evaluates the effectiveness of simple and expert searches in Google Scholar (GS), EconLit, GEOBASE, PAIS, POPLINE, PubMed, Social Sciences Citation Index, Social Sciences Full Text, and Sociological Abstracts. It assesses the recall and precision of 32 searches in the field of later-life migration: nine simple keyword searches and 23 expert searches constructed by demography librarians at three top universities. For simple searches, Google Scholar’s recall and precision are well above average. For expert searches, the relative effectiveness of GS depends on the number of results users are willing to examine. Although Google Scholar’s expert-search performance is just average within the first fifty search results, GS is one of the few databases that retrieves relevant results with reasonably high precision after the fiftieth hit. The results also show that simple searches in GS, GEOBASE, PubMed, and Sociological Abstracts have consistently higher recall and precision than expert searches. This can be attributed not to differences in expert-search effectiveness, but to the unusually strong performance of simple searches in those four databases.