Web search engines rarely agree on what the best search results are, and the disagreement have become worse over the last two years, according to new research.
In a study of 19,332 queries, Google, Yahoo, Windows Live and Ask delivered the same top result only 3.6 percent of the time. The four never delivered the same top three results. Fewer than 1 percent of first-page results were shared by all four sites.
The search engines agreed more often in a study two years ago, in which the top result matched all four engines on 7 percent of queries.
"These differences contradict any notion that all search engines are the same and that searching one engine will yield the absolute best results of the web," the paper states.
Dogpile.com, a meta-search engine that combines results from the top search sites, conducted the study with researchers from Queensland University of Technology and Pennsylvania State University. The research claims to highlight the value of sites, like Dogpile, that deliver results from multiple search engines.
The research spurred an executive with Ask.com to discuss the importance of knowing the strengths and weaknesses of each search tool, even for users who search only one engine each time they need information.
"We like to think of search engine overlap with a 'classical' library mindset. Libraries often acquire (for a fee) more than one reference book or electronic database that contain the same data, journal indexing. However, each database or book might offer different features, different ways of indexing. In other words, it's worth the money to offer, know about, and use a variety of tools. No one resource is ideal for each query," states a posting this week on ResourceShelf, a daily electronic newsletter for online researchers. The newsletter is written by Gary Price, a librarian and director of online information for Ask.com.