Equation 14 · Part 1 · From BM25 to Agentic Retrieval: A History of Retrieval-Augmented Generation
Symbol k_1
What this part means
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol k_1→Article meaning
The passage around this formula
where f(, D) is the frequency of query term in D , |D| is the document’s length, is the average document length in the collection, and and b are tuned constants controlling term-frequency saturation and length normalization respectively. The saturation term is the substantive advance over a raw term-frequency-times-IDF score: a term’s contribution grows quickly at first and then flattens, so a document that happens to repeat a…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
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Sources cited in the article section
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