Catalano.Statistics.Distributions

Class BinomialDistribution

java.lang.Object

Catalano.Statistics.Distributions.BinomialDistribution

All Implemented Interfaces:

IDiscreteDistribution

public class BinomialDistribution
extends java.lang.Object
implements IDiscreteDistribution

Binomial probability distribution. The binomial distribution is the discrete probability distribution of the number of successes in a sequence of >n independent yes/no experiments, each of which yields success with probability p. Such a success/failure experiment is also called a Bernoulli experiment or Bernoulli trial; when n = 1, the binomial distribution is a Bernoulli distribution.

Constructor Summary

Constructors

Constructor and Description
BinomialDistribution(int trials) Initializes a new instance of the BinomialDistribution class.
BinomialDistribution(int trials, double probability) Initializes a new instance of the BinomialDistribution class.

Method Summary

Modifier and Type	Method and Description
double	DistributionFunction(int k) Gets the cumulative distribution function (cdf) for this distribution evaluated at point k.
double	Entropy() Gets the entropy for this distribution.
int	getNumberOfTrials() Gets the number of trials n for the distribution.
double	getProbability() Gets the success probability p for the distribution.
double	LogProbabilityMassFunction(int k) Gets the log-probability mass function (pmf) for this distribution evaluated at point x.
double	Mean() Gets the mean for this distribution.
double	ProbabilityMassFunction(int k) Gets the probability mass function (pmf) for this distribution evaluated at point x.
double	Variance() Gets the variance for this distribution.

Methods inherited from class java.lang.Object

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

Constructor Detail

BinomialDistribution

public BinomialDistribution(int trials)

Initializes a new instance of the BinomialDistribution class.

Parameters:

trials - The number of trials n.

BinomialDistribution

public BinomialDistribution(int trials,
                            double probability)

Initializes a new instance of the BinomialDistribution class.

Parameters:

trials - The number of trials n.

probability - The success probability p in each trial.

Method Detail

getNumberOfTrials

public int getNumberOfTrials()

Gets the number of trials n for the distribution.

Returns:

Number of trials.

getProbability

public double getProbability()

Gets the success probability p for the distribution.

Returns:

Success probability.

Mean

public double Mean()

Description copied from interface: IDiscreteDistribution

Gets the mean for this distribution.

Specified by:

Mean in interface IDiscreteDistribution

Returns:

Mean.

Variance

public double Variance()

Description copied from interface: IDiscreteDistribution

Gets the variance for this distribution.

Specified by:

Variance in interface IDiscreteDistribution

Returns:

Variance.

Entropy

public double Entropy()

Description copied from interface: IDiscreteDistribution

Gets the entropy for this distribution.

Specified by:

Entropy in interface IDiscreteDistribution

Returns:

Entropy.

DistributionFunction

public double DistributionFunction(int k)

Description copied from interface: IDiscreteDistribution

Gets the cumulative distribution function (cdf) for this distribution evaluated at point k. The Cumulative Distribution Function (CDF) describes the cumulative probability that a given value or any value smaller than it will occur.

Specified by:

DistributionFunction in interface IDiscreteDistribution

Parameters:

k - A single point in the distribution range.

Returns:

Result.

ProbabilityMassFunction

public double ProbabilityMassFunction(int k)

Description copied from interface: IDiscreteDistribution

Gets the probability mass function (pmf) for this distribution evaluated at point x. The Probability Mass Function (PMF) describes the probability that a given value k will occur.

Specified by:

ProbabilityMassFunction in interface IDiscreteDistribution

Parameters:

k - A single point in the distribution range.

Returns:

The probability of k occurring in the current distribution.

LogProbabilityMassFunction

public double LogProbabilityMassFunction(int k)

Description copied from interface: IDiscreteDistribution

Gets the log-probability mass function (pmf) for this distribution evaluated at point x. The Probability Mass Function (PMF) describes the probability that a given value k will occur.

Specified by:

LogProbabilityMassFunction in interface IDiscreteDistribution

Parameters:

k - A single point in the distribution range.

Returns:

The logarithm of the probability of k occurring in the current distribution.