Package elki.math.statistics.distribution

Class LogLogisticDistribution

java.lang.Object

elki.math.statistics.distribution.LogLogisticDistribution

All Implemented Interfaces:

Distribution

@Alias({"fisk","loglog"})
public class LogLogisticDistribution
extends java.lang.Object
implements Distribution

Log-Logistic distribution also known as Fisk distribution.

Since:

0.6.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	LogLogisticDistribution.Par	Parameterization class

Nested classes/interfaces inherited from interface elki.math.statistics.distribution.Distribution

Distribution.Parameterizer

Field Summary

Fields

Modifier and Type	Field	Description
(package private) double	location	Parameters: scale, location, and shape
(package private) double	scale	Parameters: scale, location, and shape
(package private) double	shape	Parameters: scale, location, and shape

Constructor Summary

Constructors

Constructor	Description
LogLogisticDistribution(double shape, double location, double scale)	Constructor.

Method Summary

Modifier and Type	Method	Description
double	cdf(double val)	Return the cumulative density function at the given value.
static double	cdf(double val, double shape, double location, double scale)	Cumulative density function.
double	getLocation()	Get the distribution location.
double	getScale()	Get the distribution scale.
double	getShape()	Get the distribution shape.
double	logpdf(double val)	Return the log density of an existing value
static double	logpdf(double val, double shape, double location, double scale)	Probability density function.
double	nextRandom(java.util.Random random)	Generate a new random value
double	pdf(double val)	Return the density of an existing value
static double	pdf(double val, double shape, double location, double scale)	Probability density function.
double	quantile(double val)	Quantile aka probit (for normal) aka inverse CDF (invcdf, cdf^-1) function.
static double	quantile(double val, double shape, double location, double scale)	Quantile function.
java.lang.String	toString()	Describe the distribution

Methods inherited from class java.lang.Object

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

Field Detail

scale

double scale

Parameters: scale, location, and shape

location

double location

Parameters: scale, location, and shape

shape

double shape

Parameters: scale, location, and shape

Constructor Detail

LogLogisticDistribution

public LogLogisticDistribution(double shape,
                               double location,
                               double scale)

Constructor.

Parameters:

shape - Shape

location - Location

scale - Scale

Method Detail

getShape

public double getShape()

Get the distribution shape.

Returns:

Shape parameter

getLocation

public double getLocation()

Get the distribution location.

Returns:

Location parameter

getScale

public double getScale()

Get the distribution scale.

Returns:

Scale parameter

pdf

public double pdf(double val)

Description copied from interface: Distribution

Return the density of an existing value

Specified by:

pdf in interface Distribution

Parameters:

val - existing value

Returns:

distribution density

pdf

public static double pdf(double val,
                         double shape,
                         double location,
                         double scale)

Probability density function.

Parameters:

val - Value

shape - Shape

location - TODO

scale - Scale

Returns:

PDF

logpdf

public double logpdf(double val)

Description copied from interface: Distribution

Return the log density of an existing value

Specified by:

logpdf in interface Distribution

Parameters:

val - existing value

Returns:

log distribution density

logpdf

public static double logpdf(double val,
                            double shape,
                            double location,
                            double scale)

Probability density function.

Parameters:

val - Value

shape - Shape

location - Location

scale - Scale

Returns:

logPDF

cdf

public double cdf(double val)

Description copied from interface: Distribution

Return the cumulative density function at the given value.

Specified by:

cdf in interface Distribution

Parameters:

val - existing value

Returns:

cumulative density

cdf

public static double cdf(double val,
                         double shape,
                         double location,
                         double scale)

Cumulative density function.

Parameters:

val - Value

shape - Shape

location - Location

scale - Scale

Returns:

CDF

quantile

public double quantile(double val)

Description copied from interface: Distribution

Quantile aka probit (for normal) aka inverse CDF (invcdf, cdf^-1) function.

Specified by:

quantile in interface Distribution

Parameters:

val - Quantile to find

Returns:

Quantile position

quantile

public static double quantile(double val,
                              double shape,
                              double location,
                              double scale)

Quantile function.

Parameters:

val - Value

shape - Shape

location - TODO

scale - Scale

Returns:

Quantile

nextRandom

public double nextRandom(java.util.Random random)

Description copied from interface: Distribution

Generate a new random value

Specified by:

nextRandom in interface Distribution

Parameters:

random - Random number generator

Returns:

new random value

toString

public java.lang.String toString()

Description copied from interface: Distribution

Describe the distribution

Specified by:

toString in interface Distribution

Overrides:

toString in class java.lang.Object

Returns:

description