SSJ
3.3.1
Stochastic Simulation in Java
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Extends the class ContinuousDistribution for a distribution from the Pareto family, with shape parameter \(\alpha> 0\) and location parameter \(\beta> 0\) [99] (page 574). More...
Public Member Functions | |
ParetoDist (double alpha) | |
Constructs a ParetoDist object with parameters \(\alpha=\) alpha and \(\beta= 1\). | |
ParetoDist (double alpha, double beta) | |
Constructs a ParetoDist object with parameters \(\alpha=\) alpha and \(\beta= \) beta . | |
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. | |
double | getAlpha () |
Returns the parameter \(\alpha\). | |
double | getBeta () |
Returns the parameter \(\beta\). | |
void | setParams (double alpha, double beta) |
Sets the parameter \(\alpha\) and \(\beta\) for this object. | |
double [] | getParams () |
Return a table 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 alpha, double beta, double x) |
Computes the density function. | |
static double | cdf (double alpha, double beta, double x) |
Computes the distribution function. | |
static double | barF (double alpha, double beta, double x) |
Computes the complementary distribution function. | |
static double | inverseF (double alpha, double beta, double u) |
Computes the inverse of the distribution function. | |
static double [] | getMLE (double[] x, int n) |
Estimates the parameters \((\alpha,\beta)\) of the Pareto distribution using the maximum likelihood method, from the \(n\) observations \(x[i]\), \(i = 0, 1,…, n-1\). More... | |
static ParetoDist | getInstanceFromMLE (double[] x, int n) |
Creates a new instance of a Pareto distribution with parameters \(\alpha\) and \(\beta\) estimated using the maximum likelihood method based on the \(n\) observations \(x[i]\), \(i = 0, 1, …, n-1\). More... | |
static double | getMean (double alpha, double beta) |
Computes and returns the mean \(E[X] = \alpha\beta/(\alpha- 1)\) of the Pareto distribution with parameters \(\alpha\) and \(\beta\). More... | |
static double | getVariance (double alpha, double beta) |
Computes and returns the variance \(\mbox{Var}[X] = \frac{\alpha\beta^2}{(\alpha- 2)(\alpha- 1)}\) of the Pareto distribution with parameters \(\alpha\) and \(\beta\). More... | |
static double | getStandardDeviation (double alpha, double beta) |
Computes and returns the standard deviation of the Pareto distribution with parameters \(\alpha\) and \(\beta\). More... | |
Additional Inherited Members | |
Public Attributes inherited from ContinuousDistribution | |
int | decPrec = 15 |
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 |
Extends the class ContinuousDistribution for a distribution from the Pareto family, with shape parameter \(\alpha> 0\) and location parameter \(\beta> 0\) [99] (page 574).
The density for this type of Pareto distribution is
\[ f(x) = \frac{\alpha\beta^{\alpha}}{x^{\alpha+1}} \qquad\mbox{for }x \ge\beta, \tag{fpareto} \]
and 0 otherwise. The distribution function is
\[ F(x) = 1 - \left(\beta/x\right)^{\alpha}\qquad\mbox{for }x\ge\beta, \tag{Fpareto} \]
and the inverse distribution function is
\[ F^{-1}(u) = \beta(1 - u)^{-1/\alpha} \qquad\mbox{for } 0 \le u < 1. \]
double barF | ( | double | x | ) |
Returns \(\bar{F}(x) = 1 - F(x)\).
x | value at which the complementary distribution function is evaluated |
x
Implements Distribution.
double cdf | ( | double | x | ) |
Returns the distribution function \(F(x)\).
x | value at which the distribution function is evaluated |
x
Implements Distribution.
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Creates a new instance of a Pareto distribution with parameters \(\alpha\) and \(\beta\) estimated using the maximum likelihood method based on the \(n\) observations \(x[i]\), \(i = 0, 1, …, n-1\).
x | the list of observations to use to evaluate parameters |
n | the number of observations to use to evaluate parameters |
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Computes and returns the mean \(E[X] = \alpha\beta/(\alpha- 1)\) of the Pareto distribution with parameters \(\alpha\) and \(\beta\).
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Estimates the parameters \((\alpha,\beta)\) of the Pareto 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: [ \(\alpha\), \(\beta\)]. The maximum likelihood estimators are the values \((\hat{\alpha}, \hat{\beta})\) that satisfy the equations:
\begin{align*} \hat{\beta} & = \min_i \{x_i\} \\ \hat{\alpha} & = \frac{n}{\sum_{i=1}^n \ln\left(\frac{x_i}{\hat{\beta}\Rule{0.0pt}{5.5pt}{0.0pt}}\right)}. \end{align*}
See [99] (page 581).
x | the list of observations used to evaluate parameters |
n | the number of observations used to evaluate parameters |
double [] getParams | ( | ) |
Return a table containing the parameters of the current distribution.
This table is put in regular order: [ \(\alpha\), \(\beta\)].
Implements Distribution.
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Computes and returns the standard deviation of the Pareto distribution with parameters \(\alpha\) and \(\beta\).
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Computes and returns the variance \(\mbox{Var}[X] = \frac{\alpha\beta^2}{(\alpha- 2)(\alpha- 1)}\) of the Pareto distribution with parameters \(\alpha\) and \(\beta\).
double inverseF | ( | double | u | ) |
Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ).
u | value in the interval \((0,1)\) for which the inverse distribution function is evaluated |
u
Implements Distribution.