JSci.maths.statistics
Class GeometricDistribution

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

public final class GeometricDistribution
extends ProbabilityDistribution

The GeometricDistribution class provides an object for encapsulating geometric distributions.

Constructor Summary

GeometricDistribution(double prob)
Constructs a geometric distribution.

Method Summary

double	cumulative(double X) Cumulative geometric distribution function.
double	getMean() Returns the mean.
double	getSuccessParameter() Returns the success parameter.
double	getVariance() Returns the variance.
double	inverse(double probability) Inverse of the cumulative geometric distribution function.
double	probability(double X) Probability density function of a geometric 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

GeometricDistribution

public GeometricDistribution(double prob)

Constructs a geometric distribution.

Parameters:

prob - the probability of success.

Method Detail

getSuccessParameter

public double getSuccessParameter()

Returns the success parameter.

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 geometric distribution. P(X) = p (1-p)^X-1.

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 geometric 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 geometric distribution function.

Specified by:

inverse in class ProbabilityDistribution

Returns:

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