Abstract
Conventional search engines, such as Bing, Baidu, and Google, offer a convenient way for users to seek information on the web. However, with all the benefits they provide, one major limitation is that a sizable portion of the information sources on the web may not be available due to commercial or proprietary reasons. Federated search solves this problem by providing a single user interface through which multiple independent resources can be searched and their results are combined for end users. Up to now, federated search has become a well-established research area, with many systems developed and algorithms proposed to deal with three major issues: resource description, resource selection, and results merging. This paper reviews state-of-the-art federated search techniques developed over the past three decades, with more attention to recent achievement. Both resource selection and result merging methods are categorized into three types, heuristic, machine learning-based, and other methods. Apart from the three major issues above-mentioned, we also discuss systems and prototypes developed, and datasets used for federated search experiments. Some other related issues including retrieval evaluation, aggregated search, metasearch, supporting personalization in federated search, are also covered. Finally, we conclude by discussing some directions for future research.
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AG conceptualized the idea for the article, performed the literature search and data analysis, prepared the figures, and wrote the first draft. SW manually read and selected the papers to be included in the manuscript, restructured the manuscript, critically revised the work for important intellectual content, and proofread it. SK performed the literature search, proofread the manuscript, prepared the tables, and formatted it in Latex for journal submission.
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Garba, A., Wu, S. & Khalid, S. Federated search techniques: an overview of the trends and state of the art. Knowl Inf Syst 65, 5065–5095 (2023). https://doi.org/10.1007/s10115-023-01922-6
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DOI: https://doi.org/10.1007/s10115-023-01922-6