JSci.maths.statistics
Class BinomialDistribution

java.lang.Object
  JSci.maths.statistics.ProbabilityDistribution
      JSci.maths.statistics.BinomialDistribution

public final class BinomialDistribution
extends ProbabilityDistribution

The BinomialDistribution class provides an object for encapsulating binomial distributions.

Constructor Summary

BinomialDistribution(int trials, double prob)
Constructs a binomial distribution.

Method Summary

double	cumulative(double X) Cumulative binomial distribution function.
double	getMean() Returns the mean.
double	getProbabilityParameter() Returns the probability.
int	getTrialsParameter() Returns the number of trials.
double	getVariance() Returns the variance.
double	inverse(double probability) Inverse of the cumulative binomial distribution function.
double	probability(double X) Probability density function of a binomial distribution.

Methods inherited from class JSci.maths.statistics.ProbabilityDistribution

checkRange, checkRange, findRoot

Methods inherited from class java.lang.Object

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

Constructor Detail

BinomialDistribution

public BinomialDistribution(int trials,
                            double prob)

Constructs a binomial distribution.

Parameters:

trials - the number of trials.

prob - the probability.

Method Detail

getTrialsParameter

public int getTrialsParameter()

Returns the number of trials.

getProbabilityParameter

public double getProbabilityParameter()

Returns the probability.

getMean

public double getMean()

Returns the mean.

getVariance

public double getVariance()

Returns the variance.

probability

public double probability(double X)

Probability density function of a binomial distribution.

Specified by:

probability in class ProbabilityDistribution

Parameters:

X - should be integer-valued.

Returns:

the probability that a stochastic variable x has the value X, i.e. P(x=X).

cumulative

public double cumulative(double X)

Cumulative binomial distribution function.

Specified by:

cumulative in class ProbabilityDistribution

Parameters:

X - should be integer-valued.

Returns:

the probability that a stochastic variable x is less then X, i.e. P(x<X).

inverse

public double inverse(double probability)

Inverse of the cumulative binomial distribution function.

Specified by:

inverse in class ProbabilityDistribution

Returns:

the value X for which P(x<X).