Displaying 20 results from an estimated 20000 matches similar to: "Use of "ks.test()" function"
2004 May 06
0
help on ks.test
> -----Original Message-----
> From: Peter Dalgaard
> Sent: Thursday, May 06, 2004 4:32 PM
> To: Janete Borges
> Cc: r-help at stat.math.ethz.ch
> Subject: Re: [R] help on ks.test
>
> "Janete Borges" <janeteborges at gmx.net> writes:
>
> > Dear All
> >
> > I need to test the goodness-of-fit of a (Negative) Exponential
>
2006 Dec 15
2
ks.test "greater" and "less"
Hello r-group
I have a question to the ks.test.
I would expect different values for less and greater between data1 and
data2.
Does anybody could explain my point of misunderstanding the function?
data1<-c(8,12,43,70)
data2<- c(70,43,12,8)
ks.test(data1,"pnorm")
ks.test(data1,"pnorm",alternative ="less") #expected < 0.001
2005 Jun 27
1
ks.test() output interpretation
I'm using ks.test() to compare two different
measurement methods. I don't really know how to
interpret the output in the absence of critical value
table of the D statistic. I guess I could use the
p-value when available. But I also get the message
"cannot compute correct p-values with ties ..." does
it mean I can't use ks.test() for these data or I can
still use the D
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,
2006 Mar 18
0
How to bootstrap one-sample ks.test?
Hello!
I am testing if my data are distributed under Laplace's distribution,
which I managed to do with:
> library(rmutil)
> ks.test(jitter(x), "plaplace", mean(x), sd(x))
Nevertheless, I am trying to bootstrap ks.test without any success.
Something is wrong in my commands:
> data = read.table("data.dat",T)
> library(rmutil)
> library(boot)
> ks.laplace =
2008 Aug 12
0
KS Test for Mixture of Distributions
Hi all,
How can we use ks.test() to evaluate
goodness of fit of mixtures of distributions?
For example I have the following dataset:
> x
[1] 176.1 176.8 259.6 171.6 90.0 234.3 145.7 113.7 105.9 176.2 168.9 136.1
[13] 109.2 110.3 164.3 117.7 131.3 163.7 200.4 196.4 196.2 168.6 190.4 127.5
[25] 136.0 114.2 112.0 91.9 333.4 295.5 172.0 293.3 91.7 289.7 118.8 55.1
[37] 161.9 233.9 197.7
2024 Apr 07
0
Questions about ks.test function {stats}
Dear R-help,
Hope this email finds you well. My name is Ziyan. I am a graduate student in Zhejiang University. My subject research involves ks.test in stats-package {stats}. Based on the code, I have two main questions. Could you provide me some more information?
I download different versions of the r language source code through r language website (https://www.r-project.org/). By reading
2008 Feb 14
1
ks.test help
I am trying to do a ks.test in R 2.6.2 (running on Mac OS X 10.4.11).
In the help guides it specifies that the y variable can be a
character string for the type of distribution I want. I am doing this
on the residuals of a regression model, but I continue to get an
error. This is some of the code I have tried:
> ks.test(res,"Norm")
Error in get(y, mode =
2012 Sep 28
1
Crosstable-like analysis (ks test) of dataframe
Hi,
I have a dataframe with multiple (appr. 20) columns containing
vectors of different values (different distributions).
Now I'd like to create a crosstable
where I compare the distribution of each vector (df-column) with
each other. For the comparison I want to use the ks.test().
The result should contain as row and column names the column names
of the input dataframe and the cells should
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 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
2005 Nov 18
1
help on ks.test and shapiro.test
I have three files of data which are available at http://zhangw.com/
R/, varied at the number of data. I tried to use R to analyze using
shapiro.test, ks.test, and t.test. t.test ran as expected, however,
when I run shapiro.test and ks.test commands, error message always
occurred. Error message for
shapiro.test is
"Error in "[.data.frame"(x, complete.cases(x)) :
undefined
2010 Mar 13
1
What can I use instead of ks.test for the binomial distribution ?
Hello all,
A friend just showed me how ks.test fails to work with pbinom for small
"size".
Example:
x<-rbinom(10000,10,0.5)
x2<-rbinom(10000,10,0.5)
ks.test(x,pbinom,10,0.5)
ks.test(x,pbinom,size = 10, prob= 0.5)
ks.test(x,x2)
The tests gives significant p values, while the x did come from
binom with size = 10 prob = 0.5.
What test should I use instead ?
Thanks,
Tal
2012 Jan 04
1
KS and AD test for Generalized PAreto and Generalized Extreme value
Dear R helpers,
I need to use KS and AD test for Generalized Pareto and Generalized extreme value.
E.g. if I need to use KS for Weibull, I have teh syntax
ks.test(x.wei,"pweibull", shape=2,scale=1)
Similarly, for AD I use
ad.test(x, distr.fun, ...)
My problem is fir given data, I have estimated the parameters of GPD and GEV using lmom. But I am not able to find out the distribution
2005 Apr 07
1
ks.test for conditional distribution Y|x
Couldn't you do this by subtracting 0.5 + x from your y values and checking
for normality with mean 0 and sd = 1 (using ks.test or another test of
normality).
If you fail, you'll have to do additional work to find out whether pairs
with some particular x value (or range of x values) is causing the problem,
but I think this fits the question as stated.
Of course, if you have discrete x
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 =
2009 Jul 22
0
ks.test - The two-sample two-sided Kolmogorov-Smirnov test with ties (PR#13848)
Full_Name: Thomas Waterhouse
Version: 2.9.1
OS: OS X 10.5.7
Submission from: (NULL) (216.239.45.4)
ks.test uses a biased approximation to the p-value in the case of the two-sample
test with ties in the pooled data. This has been justified in R in the past by
the argument that the KS test assumes a continuous distribution. But the
two-sample test can be extended to arbitrary distributions by a
2012 Oct 12
1
ks.test not working?
Hi,
I am performing GEV analysis on temperature/precipitation data and want to use the ks.boot function but I am unsure of how to implement it using the pgev distribution.
For example:
ks.test(data,pgev,shape,location,scale)
ks.boot(data,(distribution parameters?),alternative="pgev",nboots=1000)
Any advice? Apologies in advance if I have used the wrong email address.
Regards,
Louise
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)
2017 Nov 15
0
ks.test() with 2 samples vs. 1 sample an distr. function
In the first example you are performing a one-sample test against a continuous cumulative distribution (in this case a normal distribution). In the second case you are performing a two-sample test. You drew your values for x non-randomly by specifying fixed intervals along a normal distribution, but ks.test() just sees that you have provided two samples, not one sample and values along a