IR-part2

We will use document frequency df to capture this

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Unformatted text preview: ant. §༊  Relevance does not increase propor*onally with term frequency. NB: frequency = count in IR Introduc)on to Informa)on Retrieval Sec. 6.2 Log- frequency weigh*ng §༊  The log frequency weight of term t in d is wt,d ⎧ྏ1 + log10 tft,d , = ⎨ྏ 0, ⎩ྏ if tft,d > 0 otherwise §༊  Score for a document- query pair: sum over terms t in both q and d: §༊  score = t∈q∩d (1 + log tft ,d ) ∑ §༊  The score is 0 if none of the query terms is present in the document. Introduc)on to Informa)on Retrieval Sec. 6.2 Log- frequency weigh*ng §༊  The log frequency weight of term t in d is wt,d ⎧ྏ1 + log10 tft,d , = ⎨ྏ 0, ⎩ྏ if tft,d > 0 otherwise §༊  0 → 0, 1 → 1, 2 → 1.3, 10 → 2, 1000 → 4, etc. §༊  Score for a document- query pair: sum over terms t in both q and d: §༊  score = t∈q∩d (1 + log tft ,d ) ∑ §༊  The score is 0 if none of the query terms is present in the document. Introduc)on to Informa)on Retrieval Introduc*on to Informa(on Retrieval Term f...
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