portal: Libraries and the Academy

This paper presents a comparative evaluation of Google Scholar and 11 other bibliographic databases (Academic Search Elite, AgeLine, ArticleFirst, EconLit, GEOBASE, MEDLINE, PAIS International, POPLINE, Social Sciences Abstracts, Social Sciences Citation Index, and SocINDEX), focusing on search performance within the multidisciplinary field of later-life migration. The results of simple keyword searches are evaluated with reference to a set of 155 relevant articles identified in advance. In terms of both recall and precision, Google Scholar performs better than most of the subscription databases. This finding, based on a rigorous evaluation procedure, is contrary to the impressions of many early reviewers. The paper concludes with a discussion of a new approach to document relevance in educational settings—an approach that accounts for the instructors' goals as well as the students' assessments of relevance.