ArangoSearch Scorers

    Details about their usage in AQL can be found in theArangoSearch section.

    • BM25: order results based on the

    IResearch provides a ‘bm25’ scorer implementing theBM25 algorithm. Optionally, freeparameters k and b of the algorithm typically using for advancedoptimization can be specified as floating point numbers.

    • k (number, optional): term frequency, the default is 1.2. k_calibrates the text term frequency scaling. A _k value of 0 corresponds toa binary model (no term frequency), and a large value corresponds to using rawterm frequency.

    • b (number, optional): determines the scaling by the total text length, thedefault is 0.75. b determines the scaling by the total text length.

      • b = 0 corresponds to no length normalization.At the extreme values of the coefficient b, BM25 turns into the rankingfunctions known as BM11 (for b = 1) and BM15 (for b = 0).

    TFIDF() - Term Frequency – Inverse Document Frequency Algorithm

    • doc (document): must be emitted by
    • withNorms (bool, optional): specifying whether norms should be used viawith-norms, the default is false