org.terrier.matching.models.normalisation
Class Normalisation0

java.lang.Object
  org.terrier.matching.models.normalisation.Normalisation
      org.terrier.matching.models.normalisation.Normalisation0

All Implemented Interfaces:

java.io.Serializable

public class Normalisation0
extends Normalisation

This class implements an empty normalisation. It does no frequency normalisation but returns the original frequency. In case of applying field retrieval, the returned value is the original frequency times the weight of the field.

Author:

Ben He

See Also:

Serialized Form

Field Summary

protected java.lang.String

methodName The name of the normalisation method .

Fields inherited from class org.terrier.matching.models.normalisation.Normalisation

averageDocumentLength, idf, Nt, numberOfDocuments, numberOfTokens, parameter, termFrequency

Constructor Summary

Normalisation0()

Method Summary

java.lang.String	getInfo() Get the name of the normalisation method.
double	normalise(double tf, double docLength, double termFrequency) This method returns the original term frequency.

Methods inherited from class org.terrier.matching.models.normalisation.Normalisation

getParameter, setAverageDocumentLength, setDocumentFrequency, setNumberOfDocuments, setNumberOfTokens, setParameter

Methods inherited from class java.lang.Object

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

Field Detail

methodName

protected final java.lang.String methodName

The name of the normalisation method .

See Also:

Constant Field Values

Constructor Detail

Normalisation0

public Normalisation0()

Method Detail

getInfo

public java.lang.String getInfo()

Get the name of the normalisation method.

Specified by:

getInfo in class Normalisation

Returns:

Return the name of the normalisation method.

normalise

public double normalise(double tf,
                        double docLength,
                        double termFrequency)

This method returns the original term frequency. If field retrieval is applied, the returned value is the original frequency times the weight of the field.

Specified by:

normalise in class Normalisation

Parameters:

tf - The frequency of the query term in the document.

docLength - The number of tokens in the document.

termFrequency - The frequency of the query term in the collection.

Returns:

The normalised term frequency.