org.terrier.matching.models.normalisation

Class NormalisationP

java.lang.Object

org.terrier.matching.models.normalisation.Normalisation

org.terrier.matching.models.normalisation.NormalisationP

All Implemented Interfaces:

Serializable, Cloneable

public class NormalisationP
extends Normalisation

This class implements Term Frequency Normalisation via Pareto Distributions

Author:

Ben He

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected 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

Constructors

Constructor and Description
NormalisationP() The default constructor.
NormalisationP(double value) Constructor that also sets the parameter z (the power in the normalisation).

Method Summary

Methods

Modifier and Type	Method and Description
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

clone, getParameter, setAverageDocumentLength, setDocumentFrequency, setNumberOfDocuments, setNumberOfTokens, setParameter

Methods inherited from class java.lang.Object

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

Field Detail

methodName

protected final String methodName

The name of the normalisation method .

See Also:

Constant Field Values

Constructor Detail

NormalisationP

public NormalisationP()

The default constructor.

NormalisationP

public NormalisationP(double value)

Constructor that also sets the parameter z (the power in the normalisation).

Parameters:

value - The specified value for the parameter z.

Method Detail

getInfo

public 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.