org.terrier.matching.models

Class DFIZ

java.lang.Object

org.terrier.matching.models.WeightingModel

org.terrier.matching.models.DFIZ

All Implemented Interfaces:

Serializable, Cloneable, Model

public class DFIZ
extends WeightingModel

Divergence From Independence model based on Standardization (i.e., standardized distance from independence in term frequency tf).

For more information:

A Nonparametric Term Weighting Method for Information Retrieval Based on Measuring the Divergence from Independence. Kocabas, Dincer & Karaoglan, International Journal of Information Retrieval, (to appear), 2013. doi: 10.1007/s10791-013-9225-4.

IRRA at TREC 2012: Index Term Weighting based on Divergence From Independence Model. Dincer, Kocabas & Karaoglan, NIST Special Publication, Proc. of the 20th Text Retrieval Conference, TREC'12, Gaitersburg, MD, USA, 2012.

Since:

3.5

Author:

Bekir Taner Dincer & Craig Macdonald

See Also:

Serialized Form

Field Summary

Fields inherited from class org.terrier.matching.models.WeightingModel

averageDocumentLength, c, cs, documentFrequency, es, i, keyFrequency, numberOfDocuments, numberOfPointers, numberOfTokens, numberOfUniqueTerms, rq, termFrequency

Constructor Summary

Constructors

Constructor and Description
DFIZ()

Method Summary

Methods

Modifier and Type	Method and Description
String	getInfo() Returns the name of the model.
double	score(double tf, double docLength) This method provides the contract for implementing weighting models.

Methods inherited from class org.terrier.matching.models.WeightingModel

clone, getOverflowed, getParameter, prepare, score, setCollectionStatistics, setEntryStatistics, setKeyFrequency, setParameter, setRequest

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DFIZ

public DFIZ()

Method Detail

getInfo

public String getInfo()

Description copied from class: WeightingModel

Returns the name of the model.

Specified by:

getInfo in interface Model

Specified by:

getInfo in class WeightingModel

Returns:

java.lang.String

score

public double score(double tf,
           double docLength)

Description copied from class: WeightingModel

This method provides the contract for implementing weighting models.

Specified by:

score in class WeightingModel

Parameters:

tf - The term frequency in the document

docLength - the document's length

Returns:

the score assigned to a document with the given tf and docLength, and other preset parameters