core/org.gnit.lucenekmp.search.similarities/AxiomaticF3EXP

AxiomaticF3EXP

class AxiomaticF3EXP(s: Float, queryLen: Int, k: Float = 0.35f) : Axiomatic

F3EXP is defined as Sum(tf(term_doc_freq)*IDF(term)-gamma(docLen, queryLen)) where IDF(t) = pow((N+1)/df(t), k) N=total num of docs, df=doc freq gamma(docLen, queryLen) = (docLen-queryLen)queryLens/avdl NOTE: the gamma function of this similarity creates negative scores

Constructors

AxiomaticF3EXP

constructor(s: Float, queryLen: Int, k: Float = 0.35f)

Properties

discountOverlaps

val discountOverlaps: Boolean

True if overlap tokens (tokens with a position of increment of zero) are discounted from the document's length.

Functions

computeNorm

open fun computeNorm(state: FieldInvertState): Long

Computes the normalization value for a field at index-time.

scorer

open override fun scorer(boost: Float, collectionStats: CollectionStatistics, vararg termStats: TermStatistics): Similarity.SimScorer

Compute any collection-level weight (e.g. IDF, average document length, etc) needed for scoring a query.

toString

open override fun toString(): String

Name of the axiomatic method.