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truncgof (version 0.6-0)

ks.test: Kolmogorov-Smirnov test

Description

Kolmogorov-Smirnov test providing a comparison of a fitted distribution with the empirical distribution.

Usage

ks.test(x, distn, fit, H = NA, alternative = c("two.sided", "less", "greater"), sim = 100, tol = 1e-04, estfun = NA)

Arguments

x
a numeric vector of data values
distn
character string naming the null distribution
fit
list of null distribution parameters
H
a treshold value
alternative
indicates the alternative hypothesis and must be one of "two.sided" (default), "less", or "greater". Initial letter must be specified only.
sim
maximum number of szenarios in the Monte-Carlo simulation
tol
if the difference of two subsequent p-value calculations is lower than tol the Monte-Carlo simulation is discontinued
estfun
an function as character string or NA (default). See mctest.

Value

A list with class "mchtest" containing the following components
statistic
the value of the Kolmogorov-Smirnov statistic
treshold
the treshold value
p.value
the p-value of the test
data.name
a character string giving the name of the data
method
the character string "Kolmorov-Smirnov test"
alternative
the alternative
sim.no
number of simulated szenarios in the Monte-Carlo simulation

Details

The Kolmogorov-Smirnov test compares the null distribution with the empirical distribution function of the observed data, where left truncated data samples are allowed. The test statistic is given by $$KS^+ = \frac{\sqrt{n}}{1-z_H}\sup_j\{z_H + \frac{j}{n}(1-z_H)-z_j\}$$ $$KS^- = \frac{\sqrt{n}}{1-z_H}\sup_j\{z_j -(z_H + \frac{j-1}{n}(1-z_H))\}$$ $$KS = \max\{KS^+, KS^-\},$$

with $z_H = F_theta(H)$ and $ z_j=F_theta(x_j)$, where $x_1, \dots, x_n$ are the ordered data values. Here, $F_theta$ is the null distribution.

References

Chernobay, A., Rachev, S., Fabozzi, F. (2005), Composites goodness-of-fit tests for left-truncated loss samples, Tech. rep., University of Calivornia Santa Barbara

See Also

ad.test, v.test, adup.test for other supremum class tests and ad2.test, ad2up.test, w2.test for quadratic class tests. For more details see mctest.

Examples

Run this code
set.seed(123)
treshold <- 10
xc  <- rlnorm(100, 2, 2)     # complete sample
xt <- xc[xc >= treshold]     # left truncated sample
ks.test(xt, "plnorm", list(meanlog = 2, sdlog = 2), H = 10)

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