edu.uah.math.distributions
Class NegativeBinomialDistribution

java.lang.Object
  edu.uah.math.distributions.Distribution
      edu.uah.math.distributions.NegativeBinomialDistribution

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

GeometricDistribution

public class NegativeBinomialDistribution
extends Distribution
implements java.io.Serializable

This class models the negative binomial distribution with specified successes parameter and probability parameter.

Version:

August, 2003

Author:

Kyle Siegrist, Dawn Duehring

See Also:

Serialized Form

Field Summary

Fields inherited from class edu.uah.math.distributions.Distribution

CONTINUOUS, DISCRETE, MIXED

Constructor Summary

NegativeBinomialDistribution()
This default constructor creates a new negative binomial distribution with successes parameter 1 and probability parameter 0.5.

NegativeBinomialDistribution(int k, double p)
This general constructor creates a new negative binomial distribution with given parameter values.

Method Summary

double	getDensity(double x) This method computes the probability density function.
double	getMaxDensity() This method computes the maximum value of the density function.
double	getMean() This method computes the mean of the distribution.
double	getMGF(double t) This method computes moment generating function.
double	getPGF(double t) This method computes the probability generating function.
double	getProbability() This method returns the probability parameter.
int	getSuccesses() This method returns the successes parameter.
double	getVariance() This method computes the variance of the distribution.
void	setParameters(int k, double p) This method set the paramters and the default domain.
void	setProbability(double p) This method sets the probability parameter.
void	setSuccesses(int k) This method set the successes parameter.
double	simulate() This method simulates a value from the distribution, overriding the correspondin default method in Distribution.
java.lang.String	toString() This method returns a string that gives the name of the distribution and the values of the parameters.

Methods inherited from class edu.uah.math.distributions.Distribution

getCDF, getDomain, getFailureRate, getMedian, getMoment, getMoment, getQuantile, getSD, getType, setDomain, setDomain

Methods inherited from class java.lang.Object

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

Constructor Detail

NegativeBinomialDistribution

public NegativeBinomialDistribution(int k,
                                    double p)

This general constructor creates a new negative binomial distribution with given parameter values.

Parameters:

k - the number of successes

p - the probability of success

NegativeBinomialDistribution

public NegativeBinomialDistribution()

This default constructor creates a new negative binomial distribution with successes parameter 1 and probability parameter 0.5.

Method Detail

setParameters

public void setParameters(int k,
                          double p)

This method set the paramters and the default domain.

Parameters:

k - the number of successes

p - the probability of success

setSuccesses

public void setSuccesses(int k)

This method set the successes parameter.

Parameters:

k - the number of successes

getSuccesses

public int getSuccesses()

This method returns the successes parameter.

Returns:

the number of successes

getProbability

public double getProbability()

This method returns the probability parameter.

Returns:

the probability of success

setProbability

public void setProbability(double p)

This method sets the probability parameter.

Parameters:

p - the probability of success

getDensity

public double getDensity(double x)

This method computes the probability density function.

Specified by:

getDensity in class Distribution

Parameters:

x - a number in the domain of the distribution

Returns:

the probability density at x

getMaxDensity

public double getMaxDensity()

This method computes the maximum value of the density function.

Overrides:

getMaxDensity in class Distribution

Returns:

the maximum value of the probability density function

getMean

public double getMean()

This method computes the mean of the distribution.

Overrides:

getMean in class Distribution

Returns:

the mean

getVariance

public double getVariance()

This method computes the variance of the distribution.

Overrides:

getVariance in class Distribution

Returns:

the variance

getPGF

public double getPGF(double t)

This method computes the probability generating function.

Overrides:

getPGF in class Distribution

Parameters:

t - a real number

Returns:

the probability generating function at t

getMGF

public double getMGF(double t)

This method computes moment generating function.

Overrides:

getMGF in class Distribution

Parameters:

t - a real number

Returns:

the moment generating function

simulate

public double simulate()

This method simulates a value from the distribution, overriding the correspondin default method in Distribution.

Overrides:

simulate in class Distribution

Returns:

a simulated value from the distribution

toString

public java.lang.String toString()

This method returns a string that gives the name of the distribution and the values of the parameters.

Overrides:

toString in class Distribution

Returns:

a string giving the name of the distribution and the values of the parameters