Displaying 20 results from an estimated 8000 matches similar to: "(PR#1007) ks.test doesn't compute correct empirical"
2001 Jul 01
0
ks.test doesn't compute correct empirical distribution if there are ties in the data (PR#1007)
Full_Name: Andrew Grant McDowell
Version: R 1.1.1 (but source in 1.3.0 looks fishy as well)
OS: Windows 2K Professional (Consumer)
Submission from: (NULL) (194.222.243.209)
In article <xeQ_6.1949$xd.353840@typhoon.snet.net>,
johnt@tman.dnsalias.com writes
>Can someone help? In R, I am generating a vector of 1000 samples from
>Bin (1000, 0.25). I then do a Kolmogorov Smirnov test
2001 Jul 03
0
(PR#1007) ks.test doesn't compute correct empirical distribution if there are ties in the data
In message <Pine.GSO.4.31.0107010731110.7616-100000@auk.stats>, Prof
Brian D Ripley <ripley@stats.ox.ac.uk> writes
>
>You do realize that the Kolmogorov tests (and the Kolmogorov-Smirnov
>extension) assume continuous distributions, so the distribution theory
>is not valid in this case?
>
>S-PLUS does stop you doing this:
>
>> ks.gof(o,
2006 Feb 03
2
Problems with ks.test
Hi everybody,
while performing ks.test for a standard exponential distribution on samples
of dimension 2500, generated everytime as new, i had this strange behaviour:
>data<-rexp(2500,0.4)
>ks.test(data,"pexp",0.4)
One-sample Kolmogorov-Smirnov test
data: data
D = 0.0147, p-value = 0.6549
alternative hypothesis: two.sided
>data<-rexp(2500,0.4)
2011 Oct 06
2
KS test and theoretical distribution
> x <- runif(100)
> y <- runif(100)
> ks.test(x,y)
Two-sample Kolmogorov-Smirnov test
data: x and y
D = 0.11, p-value = 0.5806
alternative hypothesis: two-sided
ok I expected that, but:
> ks.test(runif(100), "runif")
One-sample Kolmogorov-Smirnov test
data: runif(100)
D = 0.9106, p-value < 2.2e-16
alternative hypothesis: two-sided
How
2005 Mar 18
1
Pb with ks.test pvalue
Hello,
While doing test of normality under R and SAS, in order to prove the efficiency of R to my company, I notice
that Anderson Darling, Cramer Van Mises and Shapiro-Wilk tests results are quite the same under the two environnements,
but the Kolmogorov-smirnov p-value really is different.
Here is what I do:
> ks.test(w,pnorm,mean(w),sd(w))
One-sample Kolmogorov-Smirnov test
data: w
D
2008 Mar 08
1
ks.test troubles
Hi there!
I have two little different data. One is a computer test on people, the
other is a paper and pencil test. two boxplots show me that the data is
almost the same.
So now I'd like to know if I could handle all data as one, by testing
with ks.test:
====
> ks.test(el$angststoer, fl$angststoer)
Two-sample Kolmogorov-Smirnov test
data: el$angststoer and fl$angststoer
D =
2011 Apr 27
3
Kolmogorov-Smirnov test
Hi,
I have a problem with Kolmogorov-Smirnov test fit. I try fit distribution to
my data. Actualy I create two test:
- # First Kolmogorov-Smirnov Tests fit
- # Second Kolmogorov-Smirnov Tests fit
see below. This two test return difrent result and i don't know which is
properly. Which result is properly? The first test return lower D = 0.0234
and lower p-value = 0.00304. The lower 'D'
2001 Oct 26
1
ks.test (PR#1004)
The note to 1004 says "fixed for 1.3.1"
Uh. No. It ain't.
The problem was more serious than guessed as even the simplest testing
would show.
For example, Example 5.4 in Hollander and Wolfe (Nonparametric Statistical,
Methods, 2nd ed., Wiley, 1999, pp. 180-181)
R Version 1.3.1 (SuSE Linux 7.1)
> X <-
2002 Mar 26
3
ks.test - continuous vs discrete
I frequently want to test for differences between animal size frequency
distributions. The obvious test (I think) to use is the Kolmogorov-Smirnov
two sample test (provided in R as the function ks.test in package ctest).
The KS test is for continuous variables and this obviously includes length,
weight etc. However, limitations in measuring (e.g length to the nearest
cm/mm, weight to the nearest
2011 Jul 29
1
How to interpret Kolmogorov-Smirnov stats
Hi,
Interpretation problem ! so what i did is by using the:
>fit1 <- fitdist(vectNorm,"beta")
Warning messages:
1: In dbeta(x, shape1, shape2, log) : NaNs produced
2: In dbeta(x, shape1, shape2, log) : NaNs produced
3: In dbeta(x, shape1, shape2, log) : NaNs produced
4: In dbeta(x, shape1, shape2, log) : NaNs produced
5: In dbeta(x, shape1, shape2, log) : NaNs produced
6: In
2010 Aug 20
3
how to interpret KS test
Dear R users
I am using KS test to compare two different distribution for the same
variable (temperature) for two different time periods.
H0: the two distributions are equal
H1: the two distributions are different
ks.test (temp12, temp22)
Two-sample Kolmogorov-Smirnov test
data: temp12 and temp22
D = 0.2047, p-value < 2.2e-16
alternative hypothesis: two-sided
Warning message:
In
2011 Feb 19
3
Kolmogorov-smirnov test
Is the kolmogorov-smirnov test valid on both continuous and discrete data?
I don't think so, and the example below helped me understand why.
A suggestion on testing the discrete data would be appreciated.
Thanks,
a <- rnorm(1000, 10, 1);a # normal distribution a
b <- rnorm(1000, 12, 1.5);b # normal distribution b
c <- rnorm(1000, 8, 1);c # normal distribution c
d <- rnorm(1000,
2005 Oct 02
1
rate instead of scale in ?ks.test
I am not sure whether I'm doing something wrong or there is a bug in the
documentation of ks.test. Following the posting guide, as I'm not sure,
I haven't found this in the bug tracker, and the R FAQ says that stats
is an Add-on package of R, I think this is the place to send it.
?ks.test provides the example
<QUOTE>
# Does x come from a shifted gamma distribution with shape 3
2001 Jun 29
1
KS test in R.1.3.0 has incorrect p-values. (PR#1004)
Based on a report to the Windows maintainers from Richard Rowe
<Richard.Rowe@jcu.edu.au>:
NEWS for 1.3.0 says
o Exact p-values are available for the two-sided two-sample
Kolmogorov-Smirnov test.
I think the (new) p-values are computed but are backwards:
> set.seed(123)
> x <- rnorm(50)
> y <- runif(50)
> ks.test(x,y, exact=T)$p
[1] 1
> 1 - ks.test(x,y,
2004 Nov 01
1
ks.test calculations incorrect (PR#7330)
Full_Name: t. avery
Version: 2.0.0
OS: windows xp / Linux
Submission from: (NULL) (131.162.134.159)
ks.test does not produce the correct output.
If given the script:
d1 <- c(53.63984674,0.383141762,1.915708812,0.383141762,10.72796935,6.896551724,20.30651341,5.747126437,0)
d1
d2 <- c(76.43312102,15.2866242,3.821656051,1.27388535,0,0.636942675,1.27388535,0.636942675,0.636942675)
d2
1999 Apr 09
2
KS test from ctest package
This question is mainly aimed at Kurt Hornik as author of the ctest package,
but I'm cc'ing it to r-help as I suspect there will be other valuable
opinions out there.
I have been attempting 2 sample Kolmogorov-Smirnov tests using the ks.test
function from the ctest package (ctest v.0.9-15, R v.0.63.3 win32). I am
comparing fish length-frequency distributions. My main reference for the
2010 Mar 09
1
ks.test; memory problems
Hi R-help,
I am interested in comparing two vectors of data
observations to see if they come from the same distrubution (and have
settled on the Kolmogorov-Smirnov test to do this)..
I'd prefer to use all my data points, but computationally speaking,
this is proving to be troublesome due to the size of my vectors (the
larger of the two is about 90 million observations). I suppose I
could
2007 Oct 03
3
P-value
Hi,
why don't you try try
ks.test(VeriSeti1, VeriSeti2)$p.value
All the best
Jenny
>How can i print only the P-Value of the kolmogorov smirnov test?
>
>
>> ks.test(VeriSeti1, VeriSeti2)
>
> Two-sample Kolmogorov-Smirnov test
>
>data: VeriSeti1 and VeriSeti2
>D = 0.5, p-value = 0.4413
>alternative hypothesis: two-sided
>
>
>This expression
2006 Jul 09
1
KS Test Warning Message
All,
Happy World Cup and Wimbledon. This morning finds me with the first
of my many daily questions.
I am running a ks.test on residuals obtained from a regression model.
I use this code:
> ks.test(Year5.lm$residuals,pnorm)
and obtain this output
One-sample Kolmogorov-Smirnov test
data: Year5.lm$residuals
D = 0.7196, p-value < 2.2e-16
alternative hypothesis: two.sided
Warning
2009 Oct 12
1
Kolmogorov smirnov test
Hi r-users,
I would like to use Kolmogorov smirnov test but in my observed data(xobs) there are ties. I got the warning message. My question is can I do something about it?
ks.test(xobs, xsyn)
Two-sample Kolmogorov-Smirnov test
data: xobs and xsyn
D = 0.0502, p-value = 0.924
alternative hypothesis: two-sided
Warning message:
In ks.test(xobs, xsyn) : cannot compute correct