The fuller name, Okapi BM25, includes the name of the first system to use it, which was the Okapi information retrieval system, implemented at London's City University[1] in the 1980s and 1990s

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S-Class Information Retrieval The empirically validated retrieval progression is BM25 then learned-sparse then dense then hybrid fusion with re-ranking

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[7] It was initially available for download from its home at the SourceForge web site

If, further, Γ is a region sufficiently close to the boundary of Ω that f is twice continuously differentiable on it, then there is an explicit formula involving the Weingarten map W x for the Jacobian of changing variables in terms of the signed distance function and nearest boundary point

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com\n |date=28 February 2020\n |access-date=18 April 2021\n}}</ref> and contributors<ref>\n{{LSR\n |url=https://github

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