de.lmu.ifi.dbs.elki.math.statistics.distribution

Class LogisticDistribution

java.lang.Object

de.lmu.ifi.dbs.elki.math.statistics.distribution.AbstractDistribution

de.lmu.ifi.dbs.elki.math.statistics.distribution.LogisticDistribution

All Implemented Interfaces:

Distribution

@Alias(value="log")
public class LogisticDistribution
extends AbstractDistribution

Logistic distribution.

Since:

0.6.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LogisticDistribution.Parameterizer Parameterization class

Field Summary

Fields

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

Fields inherited from class de.lmu.ifi.dbs.elki.math.statistics.distribution.AbstractDistribution

random

Constructor Summary

Constructors

Constructor and Description
LogisticDistribution(double location, double scale) Constructor.
LogisticDistribution(double location, double scale, java.util.Random random) Constructor.
LogisticDistribution(double location, double scale, RandomFactory random) Constructor.

Method Summary

Modifier and Type	Method and Description
double	cdf(double val) Return the cumulative density function at the given value.
static double	cdf(double val, double loc, double scale) Cumulative density function.
double	getLocation() Get the location aparameter.
double	getScale() Get the scale parameter.
static double	logcdf(double val, double loc, double scale) log Cumulative density function.
double	logpdf(double val) Return the log density of an existing value
static double	logpdf(double val, double loc, double scale) log Probability density function.
static double	logquantile(double val, double loc, double scale) log Quantile function.
double	nextRandom() Generate a new random value
double	pdf(double val) Return the density of an existing value
static double	pdf(double val, double loc, 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 loc, 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

location

double location

Parameters: location and scale

scale

double scale

Parameters: location and scale

Constructor Detail

LogisticDistribution

public LogisticDistribution(double location,
                            double scale)

Constructor.

Parameters:

location - Location

scale - Scale

LogisticDistribution

public LogisticDistribution(double location,
                            double scale,
                            java.util.Random random)

Constructor.

Parameters:

location - Location

scale - Scale

random - Random number generator

LogisticDistribution

public LogisticDistribution(double location,
                            double scale,
                            RandomFactory random)

Constructor.

Parameters:

location - Location

scale - Scale

random - Random number generator

Method Detail

getLocation

public double getLocation()

Get the location aparameter.

Returns:

location

getScale

public double getScale()

Get the scale parameter.

Returns:

scale

pdf

public double pdf(double val)

Description copied from interface: Distribution

Return the density of an existing value

Parameters:

val - existing value

Returns:

distribution density

pdf

public static double pdf(double val,
                         double loc,
                         double scale)

Probability density function.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

PDF

logpdf

public double logpdf(double val)

Description copied from interface: Distribution

Return the log density of an existing value

Parameters:

val - existing value

Returns:

log distribution density

logpdf

public static double logpdf(double val,
                            double loc,
                            double scale)

log Probability density function.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

log PDF

cdf

public double cdf(double val)

Description copied from interface: Distribution

Return the cumulative density function at the given value.

Parameters:

val - existing value

Returns:

cumulative density

cdf

public static double cdf(double val,
                         double loc,
                         double scale)

Cumulative density function.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

CDF

logcdf

public static double logcdf(double val,
                            double loc,
                            double scale)

log Cumulative density function. TODO: untested.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

log PDF

quantile

public static double quantile(double val,
                              double loc,
                              double scale)

Quantile function.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

Quantile

logquantile

public static double logquantile(double val,
                                 double loc,
                                 double scale)

log Quantile function. TODO: untested.

Parameters:

val - Value

loc - Location

scale - Scale

Returns:

Quantile

quantile

public double quantile(double val)

Description copied from interface: Distribution

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

Parameters:

val - Quantile to find

Returns:

Quantile position

nextRandom

public double nextRandom()

Description copied from interface: Distribution

Generate a new random value

Specified by:

nextRandom in interface Distribution

Overrides:

nextRandom in class AbstractDistribution

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