edu.stanford.nlp.stats

Class Gamma

java.lang.Object

edu.stanford.nlp.stats.Gamma

All Implemented Interfaces:

ProbabilityDistribution<java.lang.Double>, java.io.Serializable

public class Gamma
extends java.lang.Object
implements ProbabilityDistribution<java.lang.Double>

Represents a Gamma distribution. The way that samples are drawn is stolen from Yee Whye Teh's code. It won't give the probability of a variable because gamma is a continuous distribution. should it give the mass at that point?

Author:

Jenny Finkel

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
double	alpha

Constructor Summary

Constructors

Constructor and Description
Gamma(double alpha)

Method Summary

Modifier and Type	Method and Description
java.lang.Double	drawSample(java.util.Random random)
static java.lang.Double	drawSample(java.util.Random random, double alpha)
static double	drawSample(java.util.Random r, double a, double b)
boolean	equals(java.lang.Object o)
int	hashCode()
double	logProbabilityOf(java.lang.Double x)
double	probabilityOf(java.lang.Double x)

Methods inherited from class java.lang.Object

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

Field Detail

alpha

public final double alpha

Constructor Detail

Gamma

public Gamma(double alpha)

Method Detail

drawSample

public java.lang.Double drawSample(java.util.Random random)

Specified by:

drawSample in interface ProbabilityDistribution<java.lang.Double>

drawSample

public static java.lang.Double drawSample(java.util.Random random,
                                          double alpha)

drawSample

public static double drawSample(java.util.Random r,
                                double a,
                                double b)

probabilityOf

public double probabilityOf(java.lang.Double x)

Specified by:

probabilityOf in interface ProbabilityDistribution<java.lang.Double>

logProbabilityOf

public double logProbabilityOf(java.lang.Double x)

Specified by:

logProbabilityOf in interface ProbabilityDistribution<java.lang.Double>

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object