dcg ( scores -- dcg )
Statistics

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Vocabulary
math.statistics

Inputs

scores

a sequence

Outputs

dcg

a number

Word description
Calculates the discounted cumulative gain from a list of scores. The discounted cumulative gain can be used to compare two lists of results against each other given scores for each of the results.

See https://en.wikipedia.org/wiki/Discounted_cumulative_gain

See also
ndcg

Definition

USING: kernel math math.functions math.vectors ranges sequences
;

IN: math.statistics

: dcg ( scores -- dcg )
    dup length 1 + 2 swap [a..b] [ log 2 log /f ] map v/ sum ;