Extends the class ContinuousDistribution for the Cramér-von Mises distribution (see [54], [215], [216] ). More...
Public Member Functions | |
| CramerVonMisesDist (int n) | |
| Constructs a Cramér-von Mises distribution for a sample of size \(n\). | |
| 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. | |
| int | getN () |
| Returns the parameter \(n\) of this object. | |
| void | setN (int n) |
| Sets the parameter \(n\) of this object. | |
| double[] | getParams () |
| Return an array containing the parameter \(n\) of this object. | |
| 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 (int n, double x) |
| Computes the density function for a Cramér-von Mises distribution with parameter \(n\). | |
| static double | cdf (int n, double x) |
| Computes the Cramér-von Mises distribution function with parameter. | |
| static double | barF (int n, double x) |
| Computes the complementary distribution function \(\bar{F}_n(x)\) with parameter \(n\). | |
| static double | inverseF (int n, double u) |
| Computes \(x = F_n^{-1}(u)\), where \(F_n\) is the Cramér-von Mises distribution with parameter \(n\). | |
| static double | getMean (int n) |
| Returns the mean of the distribution with parameter \(n\). | |
| static double | getVariance (int n) |
| Returns the variance of the distribution with parameter \(n\). | |
| static double | getStandardDeviation (int n) |
| Returns the standard deviation of the distribution with parameter. | |
Extends the class ContinuousDistribution for the Cramér-von Mises distribution (see [54], [215], [216] ).
Given a sample of \(n\) independent uniforms \(U_i\) over \([0,1]\), the Cramér-von Mises statistic \(W_n^2\) is defined by
\[ W_n^2 = \frac{1}{12n} + \sum_{j=1}^n \left(U_{(j)} - \frac{(j-0.5)}{n}\right)^2, \tag{CraMis} \]
where the \(U_{(j)}\) are the \(U_i\) sorted in increasing order. The distribution function (the cumulative probabilities) is defined as \(F_n(x) = P[W_n^2 \le x]\).
Definition at line 46 of file CramerVonMisesDist.java.
| umontreal.ssj.probdist.CramerVonMisesDist.CramerVonMisesDist | ( | int | n | ) |
Constructs a Cramér-von Mises distribution for a sample of size \(n\).
Definition at line 67 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.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 79 of file CramerVonMisesDist.java.
|
static |
Computes the complementary distribution function \(\bar{F}_n(x)\) with parameter \(n\).
Definition at line 220 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.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 75 of file CramerVonMisesDist.java.
|
static |
Computes the Cramér-von Mises distribution function with parameter.
\(n\). Returns an approximation of \(P[W_n^2 \le x]\), where \(W_n^2\) is the Cramér von Mises statistic (see [215], [216], [6], [106] ). The approximation is based on the distribution function of \(W^2 = \lim_{n\to\infty} W_n^2\), which has the following series expansion derived by Anderson and Darling [6] :
\[ \qquad P(W^2 \le x) = \frac{1}{\pi\sqrt{x}} \sum_{j=0}^{\infty}(-1)^j \binom{-1/2}{j} \sqrt{4j+1}\;\; {exp}\left\{-\frac{(4j+1)^2}{16 x}\right\} K_{1/4}\left(\frac{(4j+1)^2}{16 x}\right), \]
where \(K_{\nu}\) is the modified Bessel function of the second kind. To correct for the deviation between \(P(W_n^2\le x)\) and \(P(W^2\le x)\), we add a correction in \(1/n\), obtained empirically by simulation. For \(n = 10\), 20, 40, the error is less than 0.002, 0.001, and 0.0005, respectively, while for \(n \ge100\) it is less than 0.0005. For \(n \to\infty\), we estimate that the method returns at least 6 decimal digits of precision. For \(n = 1\), the method uses the exact distribution: \(P(W_1^2 \le x) = 2 \sqrt{x - 1/12}\) for \(1/12 \le x \le1/3\).
Definition at line 142 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.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 71 of file CramerVonMisesDist.java.
|
static |
Computes the density function for a Cramér-von Mises distribution with parameter \(n\).
Definition at line 103 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.getMean | ( | ) |
Returns the mean.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 87 of file CramerVonMisesDist.java.
|
static |
Returns the mean of the distribution with parameter \(n\).
Definition at line 251 of file CramerVonMisesDist.java.
| int umontreal.ssj.probdist.CramerVonMisesDist.getN | ( | ) |
Returns the parameter \(n\) of this object.
Definition at line 276 of file CramerVonMisesDist.java.
| double[] umontreal.ssj.probdist.CramerVonMisesDist.getParams | ( | ) |
Return an array containing the parameter \(n\) of this object.
Implements umontreal.ssj.probdist.Distribution.
Definition at line 294 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.getStandardDeviation | ( | ) |
Returns the standard deviation.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 95 of file CramerVonMisesDist.java.
|
static |
Returns the standard deviation of the distribution with parameter.
\(n\).
Definition at line 269 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.getVariance | ( | ) |
Returns the variance.
Reimplemented from umontreal.ssj.probdist.ContinuousDistribution.
Definition at line 91 of file CramerVonMisesDist.java.
|
static |
Returns the variance of the distribution with parameter \(n\).
Definition at line 260 of file CramerVonMisesDist.java.
| double umontreal.ssj.probdist.CramerVonMisesDist.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 83 of file CramerVonMisesDist.java.
|
static |
Computes \(x = F_n^{-1}(u)\), where \(F_n\) is the Cramér-von Mises distribution with parameter \(n\).
Definition at line 228 of file CramerVonMisesDist.java.
| void umontreal.ssj.probdist.CramerVonMisesDist.setN | ( | int | n | ) |
Sets the parameter \(n\) of this object.
Definition at line 283 of file CramerVonMisesDist.java.
| String umontreal.ssj.probdist.CramerVonMisesDist.toString | ( | ) |
Returns a String containing information about the current distribution.
Definition at line 302 of file CramerVonMisesDist.java.