SSJ  3.3.1
Stochastic Simulation in Java
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JohnsonSBDist Class Reference

Extends the class ContinuousDistribution for the Johnson \(S_B\) distribution [101], [118], [63]  with shape parameters \(\gamma\) and \(\delta> 0\), location parameter \(\xi\), and scale parameter \(\lambda>0\). More...

Inheritance diagram for JohnsonSBDist:
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Collaboration diagram for JohnsonSBDist:
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Public Member Functions

 JohnsonSBDist (double gamma, double delta, double xi, double lambda)
 Constructs a JohnsonSBDist object with shape parameters \(\gamma\) and \(\delta\), location parameter \(\xi\) and scale parameter \(\lambda\).
 
double density (double x)
 
double cdf (double x)
 Returns the distribution function \(F(x)\). More...
 
double barF (double x)
 Returns \(\bar{F}(x) = 1 - F(x)\). More...
 
double inverseF (double u)
 Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ). More...
 
double getMean ()
 Returns the mean of the distribution function.
 
double getVariance ()
 Returns the variance of the distribution function.
 
double getStandardDeviation ()
 Returns the standard deviation of the distribution function.
 
void setParams (double gamma, double delta, double xi, double lambda)
 Sets the value of the parameters \(\gamma\), \(\delta\), \(\xi\) and \(\lambda\) for this object.
 
- Public Member Functions inherited from JohnsonSystem
double getGamma ()
 Returns the value of \(\gamma\).
 
double getDelta ()
 Returns the value of \(\delta\).
 
double getXi ()
 Returns the value of \(\xi\).
 
double getLambda ()
 Returns the value of \(\lambda\).
 
double [] getParams ()
 Return an array containing the parameters of the current distribution. More...
 
String toString ()
 Returns a String containing information about the current distribution.
 
- Public Member Functions inherited from ContinuousDistribution
abstract double density (double x)
 Returns \(f(x)\), the density evaluated at \(x\). More...
 
double barF (double x)
 Returns the complementary distribution function. More...
 
double inverseBrent (double a, double b, double u, double tol)
 Computes the inverse distribution function \(x = F^{-1}(u)\), using the Brent-Dekker method. More...
 
double inverseBisection (double u)
 Computes and returns the inverse distribution function \(x = F^{-1}(u)\), using bisection. More...
 
double inverseF (double u)
 Returns the inverse distribution function \(x = F^{-1}(u)\). More...
 
double getMean ()
 Returns the mean. More...
 
double getVariance ()
 Returns the variance. More...
 
double getStandardDeviation ()
 Returns the standard deviation. More...
 
double getXinf ()
 Returns \(x_a\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
double getXsup ()
 Returns \(x_b\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
void setXinf (double xa)
 Sets the value \(x_a=\) xa, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
void setXsup (double xb)
 Sets the value \(x_b=\) xb, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 

Static Public Member Functions

static double density (double gamma, double delta, double xi, double lambda, double x)
 Returns the density function ( JohnsonSB-density ).
 
static double cdf (double gamma, double delta, double xi, double lambda, double x)
 Returns the distribution function ( JohnsonSB-dist ).
 
static double barF (double gamma, double delta, double xi, double lambda, double x)
 Returns the complementary distribution.
 
static double inverseF (double gamma, double delta, double xi, double lambda, double u)
 Returns the inverse of the distribution ( JohnsonSB-inverse ).
 
static double [] getMLE (double[] x, int n, double xi, double lambda)
 Estimates the parameters \((\gamma,\delta)\) of the Johnson \(S_B\) distribution, using the maximum likelihood method, from the \(n\) observations \(x[i]\), \(i = 0, 1,…, n-1\). More...
 
static JohnsonSBDist getInstanceFromMLE (double[] x, int n, double xi, double lambda)
 Creates a new instance of a JohnsonSBDist object using the maximum likelihood method based on the \(n\) observations \(x[i]\), \(i = 0, 1, …, n-1\). More...
 
static double getMean (double gamma, double delta, double xi, double lambda)
 Returns the mean [101]  of the Johnson \(S_B\) distribution with parameters \(\gamma\), \(\delta\), \(\xi\) and \(\lambda\).
 
static double getVariance (double gamma, double delta, double xi, double lambda)
 Returns the variance [63]  of the Johnson \(S_B\) distribution with parameters \(\gamma\), \(\delta\), \(\xi\) and \(\lambda\). More...
 
static double getStandardDeviation (double gamma, double delta, double xi, double lambda)
 Returns the standard deviation of the Johnson \(S_B\) distribution with parameters \(\gamma\), \(\delta\), \(\xi\), \(\lambda\). More...
 

Additional Inherited Members

- Public Attributes inherited from ContinuousDistribution
int decPrec = 15
 
- Protected Member Functions inherited from JohnsonSystem
 JohnsonSystem (double gamma, double delta, double xi, double lambda)
 Constructs a JohnsonSystem object with shape parameters \(\gamma= \mathtt{gamma}\) and \(\delta= \mathtt{delta}\), location parameter \(\xi= \mathtt{xi}\), and scale parameter \(\lambda= \mathtt{lambda}\).
 
void setParams0 (double gamma, double delta, double xi, double lambda)
 Sets the value of the parameters \(\gamma\), \(\delta\), \(\xi\) and \(\lambda\).
 
- Protected Attributes inherited from JohnsonSystem
double gamma
 
double delta
 
double xi
 
double lambda
 
- Protected Attributes inherited from ContinuousDistribution
double supportA = Double.NEGATIVE_INFINITY
 
double supportB = Double.POSITIVE_INFINITY
 
- Static Protected Attributes inherited from ContinuousDistribution
static final double XBIG = 100.0
 
static final double XBIGM = 1000.0
 
static final double [] EPSARRAY
 

Detailed Description

Extends the class ContinuousDistribution for the Johnson \(S_B\) distribution [101], [118], [63]  with shape parameters \(\gamma\) and \(\delta> 0\), location parameter \(\xi\), and scale parameter \(\lambda>0\).

Denoting \(t=(x-\xi)/\lambda\) and \(z = \gamma+ \delta\ln(t/(1-t))\), the density is

\[ f(x) = \frac{\delta e^{-z^2/2}}{\lambda t(1 - t)\sqrt{2\pi}}, \qquad\mbox{ for } \xi< x < \xi+\lambda, \tag{JohnsonSB-density} \]

and 0 elsewhere. The distribution function is

\[ F(x) = \Phi(z), \mbox{ for } \xi< x < \xi+\lambda, \tag{JohnsonSB-dist} \]

where \(\Phi\) is the standard normal distribution function. The inverse distribution function is

\[ F^{-1}(u) = \xi+ \lambda\left(1/\left(1+e^{-v(u)}\right)\right) \qquad\mbox{for } 0 \le u \le1, \tag{JohnsonSB-inverse} \]

where

\[ v(u) = [\Phi^{-1}(u) - \gamma]/\delta. \]

This class relies on the methods NormalDist.cdf01 and NormalDist.inverseF01 of NormalDist to approximate \(\Phi\) and \(\Phi^{-1}\).

Member Function Documentation

◆ barF()

double barF ( double  x)

Returns \(\bar{F}(x) = 1 - F(x)\).

Parameters
xvalue at which the complementary distribution function is evaluated
Returns
complementary distribution function evaluated at x

Implements Distribution.

◆ cdf()

double cdf ( double  x)

Returns the distribution function \(F(x)\).

Parameters
xvalue at which the distribution function is evaluated
Returns
distribution function evaluated at x

Implements Distribution.

◆ getInstanceFromMLE()

static JohnsonSBDist getInstanceFromMLE ( double []  x,
int  n,
double  xi,
double  lambda 
)
static

Creates a new instance of a JohnsonSBDist object using the maximum likelihood method based on the \(n\) observations \(x[i]\), \(i = 0, 1, …, n-1\).

Given the parameters \(\xi= \mathtt{xi}\) and \(\lambda= \mathtt{lambda}\), the parameters \(\gamma\) and \(\delta\) are estimated from the observations.

Parameters
xthe list of observations to use to evaluate parameters
nthe number of observations to use to evaluate parameters
xiparameter \(\xi\)
lambdaparameter \(\lambda\)

◆ getMLE()

static double [] getMLE ( double []  x,
int  n,
double  xi,
double  lambda 
)
static

Estimates the parameters \((\gamma,\delta)\) of the Johnson \(S_B\) distribution, using the maximum likelihood method, from the \(n\) observations \(x[i]\), \(i = 0, 1,…, n-1\).

Parameters \(\xi= \mathtt{xi}\) and \(\lambda= \mathtt{lambda}\) are known. The estimated parameters are returned in a two-element array in the order: [ \(\gamma\), \(\delta\)]. The maximum likelihood estimators are the values \((\hat{\gamma}, \hat{\delta})\) that satisfy the equations [63]  \(\hat{\gamma}= -\bar{f} / s_f\) and \(\hat{\delta}= 1/s_f\), where \(f = \ln(t/(1-t))\), \(\bar{f}\) is the sample mean of the \(f_i\), and

\[ s_f = \sqrt{\frac{1}{n} \sum_{i=0}^{n-1} (f_i - \bar{f})^2}, \]

with \(f_i = \ln(t_i/(1-t_i))\).

Parameters
xthe list of observations to use to evaluate parameters
nthe number of observations to use to evaluate parameters
xiparameter \(\xi\)
lambdaparameter \(\lambda\)
Returns
returns the parameters [ \(\hat{\gamma}\), \(\hat{\delta}\)]

◆ getStandardDeviation()

static double getStandardDeviation ( double  gamma,
double  delta,
double  xi,
double  lambda 
)
static

Returns the standard deviation of the Johnson \(S_B\) distribution with parameters \(\gamma\), \(\delta\), \(\xi\), \(\lambda\).

Returns
the standard deviation of the Johnson \(S_B\) distribution

◆ getVariance()

static double getVariance ( double  gamma,
double  delta,
double  xi,
double  lambda 
)
static

Returns the variance [63]  of the Johnson \(S_B\) distribution with parameters \(\gamma\), \(\delta\), \(\xi\) and \(\lambda\).

Returns
the variance of the Johnson \(S_B\) distribution.

◆ inverseF()

double inverseF ( double  u)

Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ).

Parameters
uvalue in the interval \((0,1)\) for which the inverse distribution function is evaluated
Returns
the inverse distribution function evaluated at u

Implements Distribution.


The documentation for this class was generated from the following file: