org.terrier.matching.models.normalisation

Class Normalisation3

java.lang.Object

org.terrier.matching.models.normalisation.Normalisation

org.terrier.matching.models.normalisation.Normalisation3

All Implemented Interfaces:

Serializable, Cloneable

public class Normalisation3
extends Normalisation

This class implements the Dirichlet Priors normalisation.

Author:

Gianni Amati, 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
Normalisation3() The default constructor.
Normalisation3(double value) The constructor that also sets the parameter mu of the Dirichlet Normalisation.

Method Summary

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

Normalisation3

public Normalisation3()

The default constructor.

Normalisation3

public Normalisation3(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 String getInfo()

Get the name of the normalisation method.

Specified by:

getInfo in class Normalisation

Returns:

Return the name of the normalisation method as a string

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.