A comparative study on overlapping of search results in metasearch engines and their common underlying search engines

PurposeThe age of the information explosion, effective access to the most relevant resources available on the internet is one of the chief concerns for users. Familiarity with types of search tools is required. One of the search tools designed to solve this problem for internet users is the metasearch engine (MSE). The purpose of this paper is to assess how far this search tool is truly effective in solving users' problems of Internet access.Design/methodology/approachThis research examines MSEs in terms of recall ratio in retrieving documents indexed and ranked highly (1–10) within their common underlying search engines (SEs). Five general MSEs in English, which are free of charge, were utilized in this research. In order to calculate the recall ratio of MSEs, five well known MSEs which have four common underlying SEs were chosen. Then, selected keywords were searched in each SE and MSE. Two lists were prepared: one list was based on the first ten results recalled by the SE, and the other was based on the first 40 results recalled by the MSE. These lists were compared with each other. An equation was utilized in this process.FindingsThe findings indicate that MSEs are more likely to find the same documents which are common in their underlying search engines.Research limitations/implicationsThis paper offers a rigorous quantitative method for comparative evaluation of MSEs.Practical implicationsFurthermore, MSEs which have a successful recall ratio are identified, which is a finding of great practical relevance to library and information practitioners helping users exploit the Internet to best effect.Originality/valueThis paper provides clear descriptive evidence for the underlying retrieval patterns of important search tools which are commonly used by internet users today.