umontreal.iro.lecuyer.probdist
Class Pearson5Dist
- java.lang.Object
-
- umontreal.iro.lecuyer.probdist.ContinuousDistribution
-
- umontreal.iro.lecuyer.probdist.Pearson5Dist
-
- All Implemented Interfaces:
- Distribution
public class Pearson5Dist extends ContinuousDistribution
THIS CLASS HAS BEEN RENAMEDInverseGammaDist.Extends the class
ContinuousDistributionfor the Pearson type V distribution with shape parameter α > 0 and scale parameter β > 0. The density function is given byf (x) = (βαexp-β/x)/(xα+1Γ(α)) for x > 0,and f (x) = 0 otherwise, where Γ is the gamma function. The distribution function is given byF(x) = 1 - FG(1/x), for x > 0,and F(x) = 0 otherwise, where FG(x) is the distribution function of a gamma distribution with shape parameter α and scale parameter β.
-
-
Field Summary
-
Fields inherited from class umontreal.iro.lecuyer.probdist.ContinuousDistribution
decPrec
-
-
Constructor Summary
Constructors Constructor and Description Pearson5Dist(double alpha, double beta)THIS CLASS HAS BEEN RENAMEDInverseGammaDist.
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method and Description doublebarF(double x)Returns the complementary distribution function.static doublebarF(double alpha, double beta, double x)Computes the complementary distribution function of a Pearson V distribution with shape parameter α and scale parameter β.doublecdf(double x)Returns the distribution function F(x).static doublecdf(double alpha, double beta, double x)Computes the density function of a Pearson V distribution with shape parameter α and scale parameter β.doubledensity(double x)Returns f (x), the density evaluated at x.static doubledensity(double alpha, double beta, double x)Computes the density function of a Pearson V distribution with shape parameter α and scale parameter β.doublegetAlpha()Returns the α parameter of this object.doublegetBeta()Returns the β parameter of this object.static Pearson5DistgetInstanceFromMLE(double[] x, int n)Creates a new instance of a Pearson V distribution with parameters α and β estimated using the maximum likelihood method based on the n observations x[i], i = 0, 1,…, n - 1.doublegetMean()Returns the mean.static doublegetMean(double alpha, double beta)Computes and returns the mean E[X] = β/(α - 1) of a Pearson V distribution with shape parameter α and scale parameter β.static double[]getMLE(double[] x, int n)Estimates the parameters (α, β) of the Pearson V distribution using the maximum likelihood method, from the n observations x[i], i = 0, 1,…, n - 1.double[]getParams()Return a table containing the parameters of the current distribution.doublegetStandardDeviation()Returns the standard deviation.static doublegetStandardDeviation(double alpha, double beta)Computes and returns the standard deviation of a Pearson V distribution with shape parameter α and scale parameter β.doublegetVariance()Returns the variance.static doublegetVariance(double alpha, double beta)Computes and returns the variance Var[X] = β2/((α -1)2(α - 2) of a Pearson V distribution with shape parameter α and scale parameter β.doubleinverseF(double u)Returns the inverse distribution function x = F-1(u).static doubleinverseF(double alpha, double beta, double u)Computes the inverse distribution function of a Pearson V distribution with shape parameter α and scale parameter β.voidsetParam(double alpha, double beta)Sets the parameters α and β of this object.java.lang.StringtoString()-
Methods inherited from class umontreal.iro.lecuyer.probdist.ContinuousDistribution
getXinf, getXsup, inverseBisection, inverseBrent, setXinf, setXsup
-
-
-
-
Constructor Detail
-
Pearson5Dist
public Pearson5Dist(double alpha, double beta)THIS CLASS HAS BEEN RENAMEDInverseGammaDist. Constructs a Pearson5Dist object with parameters α = alpha and β = beta.
-
-
Method Detail
-
density
public double density(double x)
Description copied from class:ContinuousDistributionReturns f (x), the density evaluated at x.- Specified by:
densityin classContinuousDistribution- Parameters:
x- value at which the density is evaluated- Returns:
- density function evaluated at x
-
cdf
public double cdf(double x)
Description copied from interface:DistributionReturns the distribution function F(x).- Parameters:
x- value at which the distribution function is evaluated- Returns:
- distribution function evaluated at x
-
barF
public double barF(double x)
Description copied from class:ContinuousDistributionReturns the complementary distribution function. The default implementation computes bar(F)(x) = 1 - F(x).- Specified by:
barFin interfaceDistribution- Overrides:
barFin classContinuousDistribution- Parameters:
x- value at which the complementary distribution function is evaluated- Returns:
- complementary distribution function evaluated at x
-
inverseF
public double inverseF(double u)
Description copied from class:ContinuousDistributionReturns the inverse distribution function x = F-1(u). Restrictions: u∈[0, 1].- Specified by:
inverseFin interfaceDistribution- Overrides:
inverseFin classContinuousDistribution- Parameters:
u- value at which the inverse distribution function is evaluated- Returns:
- the inverse distribution function evaluated at u
-
getMean
public double getMean()
Description copied from class:ContinuousDistributionReturns the mean.- Specified by:
getMeanin interfaceDistribution- Overrides:
getMeanin classContinuousDistribution- Returns:
- the mean
-
getVariance
public double getVariance()
Description copied from class:ContinuousDistributionReturns the variance.- Specified by:
getVariancein interfaceDistribution- Overrides:
getVariancein classContinuousDistribution- Returns:
- the variance
-
getStandardDeviation
public double getStandardDeviation()
Description copied from class:ContinuousDistributionReturns the standard deviation.- Specified by:
getStandardDeviationin interfaceDistribution- Overrides:
getStandardDeviationin classContinuousDistribution- Returns:
- the standard deviation
-
density
public static double density(double alpha, double beta, double x)Computes the density function of a Pearson V distribution with shape parameter α and scale parameter β.
-
cdf
public static double cdf(double alpha, double beta, double x)Computes the density function of a Pearson V distribution with shape parameter α and scale parameter β.
-
barF
public static double barF(double alpha, double beta, double x)Computes the complementary distribution function of a Pearson V distribution with shape parameter α and scale parameter β.
-
inverseF
public static double inverseF(double alpha, double beta, double u)Computes the inverse distribution function of a Pearson V distribution with shape parameter α and scale parameter β.
-
getMLE
public static double[] getMLE(double[] x, int n)Estimates the parameters (α, β) of the Pearson V distribution using the maximum likelihood method, from the n observations x[i], i = 0, 1,…, n - 1. The estimates are returned in a two-element array, in regular order: [α, β].- Parameters:
x- the list of observations to use to evaluate parametersn- the number of observations to use to evaluate parameters- Returns:
- returns the parameters [ hat(α), hat(β)]
-
getInstanceFromMLE
public static Pearson5Dist getInstanceFromMLE(double[] x, int n)
Creates a new instance of a Pearson V distribution with parameters α and β estimated using the maximum likelihood method based on the n observations x[i], i = 0, 1,…, n - 1.- Parameters:
x- the list of observations to use to evaluate parametersn- the number of observations to use to evaluate parameters
-
getMean
public static double getMean(double alpha, double beta)Computes and returns the mean E[X] = β/(α - 1) of a Pearson V distribution with shape parameter α and scale parameter β.
-
getVariance
public static double getVariance(double alpha, double beta)Computes and returns the variance Var[X] = β2/((α -1)2(α - 2) of a Pearson V distribution with shape parameter α and scale parameter β.
-
getStandardDeviation
public static double getStandardDeviation(double alpha, double beta)Computes and returns the standard deviation of a Pearson V distribution with shape parameter α and scale parameter β.
-
getAlpha
public double getAlpha()
Returns the α parameter of this object.
-
getBeta
public double getBeta()
Returns the β parameter of this object.
-
setParam
public void setParam(double alpha, double beta)Sets the parameters α and β of this object.
-
getParams
public double[] getParams()
Return a table containing the parameters of the current distribution. This table is put in regular order: [α, β].
-
toString
public java.lang.String toString()
- Overrides:
toStringin classjava.lang.Object
-
-
DMelt 3.0 © DataMelt by jWork.ORG