org.terrier.matching.models.normalisation
Class NormalisationF

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

All Implemented Interfaces:

java.io.Serializable

public class NormalisationF
extends Normalisation

This class implements an increasing density function for the frequency normalisation.

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

NormalisationF()
The default constructor.

NormalisationF(double value)
The constructor that also sets the parameter mu of the Dirichlet Normalisation.

Method Summary

java.lang.String	getInfo() Get the name of the normalisation method.
double	normalise(double tf, double docLength, double termFrequency) This method gets the normalised 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

NormalisationF

public NormalisationF()

The default constructor.

NormalisationF

public NormalisationF(double value)

The constructor that also sets the parameter mu of the Dirichlet Normalisation.

Parameters:

value - The specified value for the parameter mu.

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 gets the normalised term frequency.

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.