Displaying 20 results from an estimated 7000 matches similar to: "Expected Value of Residuals"
2000 Apr 04
2
Loading Problem
I'm using R0.90.1 on Win98. I'm trying to load an image I saved yesterday
but I keep getting the following error:
Error in load("C:/temp/245amData.R.RDa") : restore file corrupted -- no data
loaded
The image is 4,890KB.
The image Can anyone tell me how to solve this problem? I'm sure I saved
the image correctly.
Thanks.
Mark
Mark J. Lamias
Department of Statistics
2000 Jan 31
1
Crosstabs?
Is there an equivalent in R to the crosstabs command S-Plus? I've been
searching for a while and can't seem to find anything.
Thanks.
Mark J. Lamias
Department of Statistics
Department of Political Science
Survey Methodology Program/Survey Research Center
Institute for Social Research - University of Michigan
426 Thompson Street, Room 315
Ann Arbor, Michigan 48104-2321
(734) 647-5381
2000 Mar 07
3
Merging data.frames
On Tuesday, March 07, 2000 5:40 PM, Richard Bilonick wrote:
>I need to merge several data.frames into one data.frame. In S-Plus I would
>use
>"merge" but I don't see a merge command in R. What is the best way to
>accomplish
>this?
The easiest way to to this, I think, is as follows:
if you have several data frames, dataframe1, dataframe2, . . . , dataframen,
you
2004 Oct 15
0
Re: Testing for normality of residuals in a regression model
Dear Federico,
see:
? shapiro.test(stats) Shapiro-Wilk Normality Test
and
? jarque.bera.test(tseries)
Jarque-Bera Test
They are the most common tests used for normality
testing.
Ciao
Vito
Federico Gherardini wrote on Fri Oct 15 14:44:18 CEST
2004:
Hi all,
Is it possible to have a test value for assessing the
normality of
residuals from a linear regression model,
2006 Jun 13
1
Cramer-von Mises normality test
Hi, this is my first help request so please bear with me.
I've been running some normality tests using the nortest package. For
some of my datasets the Cramer-von Mises normality test generates an
extremely high probability (e.g., 1.637e+31) and indicates normality
when the other tests do not. Is there something I'm misunderstanding
or potentially a bug in the code?
Below are the
2006 Jun 14
1
Bug in nortest cvm.test package (PR#8980)
I believe there to be a bug in the cvm.test module of the nortest
package authored by Juergen Gross. I do not know how to contact the
author directly.
I've been running some normality tests using the nortest package. For
some of my datasets the Cramer-von Mises normality test generates an
extremely high probability (e.g., 1.637e+31) and indicates normality
when the other tests do
2000 Feb 23
0
Thank you!
Thank you very much for your help, your fuction runs on R without
any change, and the results are the same that your obtain with Splus,
but there still a small difference.
In SAS
W=0.960439
With your shapiro.wilk.test
W=0.9606107
But the p-values are almost the same.
Thank you very much for your help.
> Here is a function for the Shapiro-wilk test that I obtained from StatLib.
> Using
2008 Apr 26
0
Consistency of m-shapiro.test
Hello all,
I tried several experiments with the mshapiro.test package in R and compared
it with the energy package to test for multivariate normality and find that
the mshapiro.test is not consistent which is a bit concerning and has
suspicious behavior. On the other hand the energy test seems to be a more
appropriate test for testing multivariate normality in any dimension. I
looked for the
2011 Mar 14
0
Non-constancy of variances in mixed model.
Hi, I've been doing an experiment, measuring the dead-zone-diameters of
bacteria, when they've been grown with paper diffusion disks of
antimicrobial. There are two groups, or treatments - one is bacteria
that have been cultured in said antimicrobial for the past year, the
other group is of the same species, but lab stock and has not gone had
any prior contact with the antimicrobial.
2006 Jul 12
2
shapiro.test() output
R Users:
My question is probably more about elementary statistics than the
mechanics of using R, but I've been dabbling in R (version 2.2.0) and
used it recently to test some data .
I have a relatively small set of observations (n = 12) of arsenic
concentrations in background groundwater and wanted to test my
assumption of normality. I used the Shapiro-Wilk test (by calling
shapiro.test()
2010 May 11
3
Improving loop performance
R-users,
I have the following piece of code which I am trying to run on a dataframe (aga2) with about a half million records. While the code works, it is extremely slow. I've read some of the help archives indicating that I should allocate space to the p1 and ags1 vectors, which I have done, but this doesn't seem to improve speed much. Would anyone be able to provide me with advice on
2009 Oct 22
1
Normality test
I am having a hard time interpreting the results of the 'shapiro.test' for normality. If I do ?shapiro.test I see two examples using rnorm and runif. When I run the test using rnorm I get a wide variation of results. Most of this may be from variability of rnorm, samll sample size (limited to 5000 for the test), etc but if I repeat the test multiple times I can get:
>
2008 Nov 21
1
question about shapiro.test()
Hi all!
I tried to perform Shapiro-Wilk test for my sample of 243 values.
> Us
[1] -10.4 -13.1 -12.2 38.1 -18.8 -13.3 -11.7 29.3 49.7 6.8 12.7 16.3
[13] 5.8 -0.7 -29.4 4.1 38.8 -1.4 8.8 15.6 32.9 -5.3 19.1 35.8
[25] 4.0 -1.5 0.6 -4.2 -10.0 -4.0 1.1 48.9 -21.0 -5.3 5.8 -10.8
[37] 21.9 8.2 -3.2 -3.9 -2.3 12.6 -4.7 -8.0 11.8 27.4 -9.5 -20.8
[49]
2004 Jul 21
2
Testing autocorrelation & heteroskedasticity of residuals in ts
Hi,
I'm dealing with time series. I usually use stl() to
estimate trend, stagionality and residuals. I test for
normality of residuals using shapiro.test(), but I
can't test for autocorrelation and heteroskedasticity.
Is there a way to perform Durbin-Watson test and
Breusch-Pagan test (or other simalar tests) for time
series?
I find dwtest() and bptest() in the package lmtest,
but it
2008 Jan 29
1
Help needed on Normality test
Hi all T gurus,
I would like to test if my dataset is indeed from N(0, 0.011908969).
K.S. test gives following result:
> ks.test(data, "pnorm", 0, 0.011908969)
One-sample Kolmogorov-Smirnov test
data: data
D = 0.1092, p-value = 1.318e-05
alternative hypothesis: two-sided
How ever "Shapiro-Wilk" test give following :
>
2000 Oct 07
2
Possible bug in apply()
In the course of applying Shapiro-Wilk to 100,000 samples of 60 items
from 100,000 different distributions, I encountered a fatal error in
apply(). This can be reconstructed as follows, using the attached data
file distr.dat containing 2 lines of my original 100,000-line file:
> version
_
platform Windows
arch x86
os Win32
system x86, Win32
status
2008 Jul 12
5
shapiro wilk normality test
Hi everybody,
somehow i dont get the shapiro wilk test for normality. i just can?t
find what the H0 is .
i tried :
shapiro.test(rnorm(5000))
Shapiro-Wilk normality test
data: rnorm(5000)
W = 0.9997, p-value = 0.6205
If normality is the H0, the test says it?s probably not normal, doesn
?t it ?
5000 is the biggest n allowed by the test...
are there any other test ? ( i know qqnorm
2012 Apr 04
1
Shapiro-Wilk cpoefficients: 2 Qs
Greetings!
I want to have the coefficients that R uses in shapiro.test()
for the Shapiro-Wilk test for a prticular sample size, i.e.
the a[i] in
W = Sum(a[i]*x[i])/(Sum(x[i] - mean(x))^2)
(where the x[i] are sorted). Two questions:
Q1:
Is there a readymade R function from which I can extract these?
Q2:
I was wondering if I might be able to modify the code for the
function shapiro.test() so
2010 May 12
2
R version of SAS/IntrNet
Does an R package exist that is similar to SAS/Intrnet (http://support.sas.com/documentation/onlinedoc/intrnet/index.html) that will allow users to take parameters passed to it by a web request, produce results and return them to the web-browser in HTML format? I tried looking through the package descriptions, but didnt' see anything like this. Any direction or suggestions you could provide
2011 Dec 09
3
Help with Error: POSIX collating elements are not supported
Hello,
I hope this is the right place to get help fixing an error when using
Markdown on our servers.
I'm not sure what our webmasters have done, but a recent change (perhaps to
PHP?) made our Markdown text disappear from the page because of an error.
PHP Warning: preg_replace_callback() [<a
href='function.preg-replace-callback'>function.preg-replace-callback</a>]: