Extends the class ContinuousDistribution for the Log-Logistic distribution with shape parameter \(\alpha> 0\) and scale parameter. More...
Public Member Functions | |
| LoglogisticDist (double alpha, double beta) | |
| Constructs a log-logistic distribution with parameters \(\alpha\) and \(\beta\). | |
| double | density (double x) |
| Returns \(f(x)\), the density evaluated at \(x\). | |
| double | cdf (double x) |
| Returns the distribution function \(F(x)\). | |
| double | barF (double x) |
| Returns the complementary distribution function. | |
| double | inverseF (double u) |
| Returns the inverse distribution function \(x = F^{-1}(u)\). | |
| double | getMean () |
| Returns the mean. | |
| double | getVariance () |
| Returns the variance. | |
| double | getStandardDeviation () |
| Returns the standard deviation. | |
| double | getAlpha () |
| Return the parameter \(\alpha\) of this object. | |
| double | getBeta () |
| Returns the parameter \(\beta\) of this object. | |
| void | setParams (double alpha, double beta) |
| Sets the parameters \(\alpha\) and \(\beta\) of this object. | |
| double[] | getParams () |
| Return a table containing the parameters of the current distribution. | |
| String | toString () |
| Returns a String containing information about the current distribution. | |
| Public Member Functions inherited from umontreal.ssj.probdist.ContinuousDistribution | |
| double | inverseBrent (double a, double b, double u, double tol) |
| Computes the inverse distribution function \(x = F^{-1}(u)\), using the Brent-Dekker method. | |
| double | inverseBisection (double u) |
| Computes and returns the inverse distribution function \(x = F^{-1}(u)\), using bisection. | |
| double | getXinf () |
| Returns \(x_a\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). | |
| double | getXsup () |
| Returns \(x_b\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). | |
| void | setXinf (double xa) |
| Sets the value \(x_a=\) xa, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). | |
| void | setXsup (double xb) |
| Sets the value \(x_b=\) xb, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). | |
Static Public Member Functions | |
| static double | density (double alpha, double beta, double x) |
Computes the density function ( floglogistic ) for a log-logisitic distribution with parameters. | |
| static double | cdf (double alpha, double beta, double x) |
Computes the distribution function ( Floglogistic ) of the log-logistic distribution with parameters. | |
| static double | barF (double alpha, double beta, double x) |
Computes the complementary distribution function ( Fbarloglogistic ) of the log-logistic distribution with parameters. | |
| static double | inverseF (double alpha, double beta, double u) |
| Computes the inverse of the log-logistic distribution with parameters \(\alpha\) and \(\beta\). | |
| static double[] | getMLE (double[] x, int n) |
| Estimates the parameters \((\alpha,\beta)\) of the log-logistic distribution using the maximum likelihood method, from the \(n\) observations \(x[i]\), \(i = 0, 1,…, n-1\). | |
| static LoglogisticDist | getInstanceFromMLE (double[] x, int n) |
| Creates a new instance of a log-logistic distribution with parameters \(\alpha\) and \(\beta\) estimated using the maximum likelihood method based on the \(n\) observations. | |
| static double | getMean (double alpha, double beta) |
| Computes and returns the mean \(E[X] = \beta\theta \mbox{cosec}(\theta),
\mbox{ where } \theta= \pi/\alpha,\) of the log-logistic distribution with parameters \(\alpha\) and. | |
| static double | getVariance (double alpha, double beta) |
| Computes and returns the variance. | |
| static double | getStandardDeviation (double alpha, double beta) |
| Computes and returns the standard deviation of the log-logistic distribution with parameters \(\alpha\) and \(\beta\). | |
Extends the class ContinuousDistribution for the Log-Logistic distribution with shape parameter \(\alpha> 0\) and scale parameter.
\[ f(x) = \frac{\alpha(x / \beta)^{\alpha- 1}}{\beta[1 + (x / \beta)^{\alpha}]^2} \qquad\qquad\mbox{for } x > 0 \tag{floglogistic} \]
and its distribution function is
\[ F(x) = \frac{1}{1 + (\frac{x}{\beta})^{-\alpha}} \qquad\qquad\mbox{for } x > 0. \tag{Floglogistic} \]
The complementary distribution is
\[ \bar{F}(x) = \frac{1}{1 + (\frac{x}{\beta})^{\alpha}} \qquad\qquad\mbox{for } x > 0. \tag{Fbarloglogistic} \]
Definition at line 49 of file LoglogisticDist.java.
| umontreal.ssj.probdist.LoglogisticDist.LoglogisticDist | ( | double | alpha, |
| double | beta ) |
Constructs a log-logistic distribution with parameters \(\alpha\) and \(\beta\).
Definition at line 89 of file LoglogisticDist.java.
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static |
Computes the complementary distribution function ( Fbarloglogistic ) of the log-logistic distribution with parameters.
\(\alpha\) and \(\beta\).
Definition at line 181 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.barF | ( | double | x | ) |
Returns the complementary distribution function.
The default implementation computes \(\bar{F}(x) = 1 - F(x)\).
| x | value at which the complementary distribution function is evaluated |
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 101 of file LoglogisticDist.java.
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static |
Computes the distribution function ( Floglogistic ) of the log-logistic distribution with parameters.
\(\alpha\) and \(\beta\).
Definition at line 158 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.cdf | ( | double | x | ) |
Returns the distribution function \(F(x)\).
| x | value at which the distribution function is evaluated |
Implements umontreal.ssj.probdist.Distribution.
Definition at line 97 of file LoglogisticDist.java.
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static |
Computes the density function ( floglogistic ) for a log-logisitic distribution with parameters.
\(\alpha\) and \(\beta\).
Definition at line 128 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.density | ( | double | x | ) |
Returns \(f(x)\), the density evaluated at \(x\).
| x | value at which the density is evaluated |
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 93 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.getAlpha | ( | ) |
Return the parameter \(\alpha\) of this object.
Definition at line 352 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.getBeta | ( | ) |
Returns the parameter \(\beta\) of this object.
Definition at line 359 of file LoglogisticDist.java.
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static |
Creates a new instance of a log-logistic 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 |
Definition at line 287 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.getMean | ( | ) |
Returns the mean.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 109 of file LoglogisticDist.java.
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static |
Computes and returns the mean \(E[X] = \beta\theta \mbox{cosec}(\theta), \mbox{ where } \theta= \pi/\alpha,\) of the log-logistic distribution with parameters \(\alpha\) and.
\(\beta\).
Definition at line 301 of file LoglogisticDist.java.
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static |
Estimates the parameters \((\alpha,\beta)\) of the log-logistic 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 estimate of the parameters is given by maximizing numerically the log-likelihood function, using the Uncmin package [203], [224] .
| x | the list of observations to use to evaluate parameters |
| n | the number of observations to use to evaluate parameters |
Definition at line 236 of file LoglogisticDist.java.
| double[] umontreal.ssj.probdist.LoglogisticDist.getParams | ( | ) |
Return a table containing the parameters of the current distribution.
This table is put in regular order: [ \(\alpha\), \(\beta\)].
Implements umontreal.ssj.probdist.Distribution.
Definition at line 381 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.getStandardDeviation | ( | ) |
Returns the standard deviation.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 117 of file LoglogisticDist.java.
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static |
Computes and returns the standard deviation of the log-logistic distribution with parameters \(\alpha\) and \(\beta\).
Definition at line 345 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.getVariance | ( | ) |
Returns the variance.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 113 of file LoglogisticDist.java.
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static |
Computes and returns the variance.
\(\mbox{Var}[X] = \beta^2 \theta(2 \mbox{cosec}(2 \theta) - \theta[\mbox{cosec}(\theta)]^2), \mbox{ where } \theta= {\pi/\alpha},\) of the log-logistic distribution with parameters \(\alpha\) and \(\beta\).
Definition at line 326 of file LoglogisticDist.java.
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static |
Computes the inverse of the log-logistic distribution with parameters \(\alpha\) and \(\beta\).
Definition at line 204 of file LoglogisticDist.java.
| double umontreal.ssj.probdist.LoglogisticDist.inverseF | ( | double | u | ) |
Returns the inverse distribution function \(x = F^{-1}(u)\).
Restrictions: \(u \in[0,1]\).
| u | value at which the inverse distribution function is evaluated |
| IllegalArgumentException | if \(u\) is not in the interval \([0,1]\) |
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 105 of file LoglogisticDist.java.
| void umontreal.ssj.probdist.LoglogisticDist.setParams | ( | double | alpha, |
| double | beta ) |
Sets the parameters \(\alpha\) and \(\beta\) of this object.
Definition at line 366 of file LoglogisticDist.java.
| String umontreal.ssj.probdist.LoglogisticDist.toString | ( | ) |
Returns a String containing information about the current distribution.
Definition at line 389 of file LoglogisticDist.java.