Displaying 20 results from an estimated 7000 matches similar to: "Randomization tests"
2000 Nov 01
0
Loop elimination question
How about:
> dim
[1] 3 1 4 1 5
> N <- length(dim)
> one <- rep(c(3,4),N)
> two <- c(rep(1,N),dim)
> three <- rep(1:N,rep(2,N))+N*rep(0:1,N)
> rep(one,two[three])
[1] 3 4 4 4 3 4 3 4 4 4 4 3 4 3 4 4 4 4 4
----------------------
Bendix Carstensen
Senior Statistician
Steno Diabetes Centre
Niels Steensens Vej 2
DK-2820 Gentofte
Denmark
tel: +45 44 43 87 38
mob: +45 28
2000 Aug 20
1
Best subsets regression
Hi all,
has anyone written a function to do "best subsets" regression similar to
the Minitab command?
Regards,
Murray Jorgensen
Murray Jorgensen, Department of Statistics, U of Waikato, Hamilton, NZ
-----[+64-7-838-4773]---------------------------[maj at waikato.ac.nz]-----
"Doubt everything or believe everything:these are two equally convenient
strategies. With either we
2001 May 22
2
MASS data sets
I'm running R 1.2.2 under windows 98 on a Pentium 133 laptop.
I can't seem to retrieve the package MASS data sets:
> library(MASS)
> data(wtloss)
Warning message:
Data set `wtloss' not found in: data(wtloss)
> data(abbey)
Warning message:
Data set `abbey' not found in: data(abbey)
And yet all the .rda files for the MASS datasets are in
D:\Program
1999 Sep 02
0
Plotting slowly
Some older members of this list will remember the strange pleasure of
seeing a pattern slowly emerge as points were laboriously added to a
scatterplot on graph paper.
A colleague (Harold Henderson, in fact) recently pointed out to me that
there is some quite interesting structure in the abrasion loss data set of
O. L. Davies (reprinted in the book by Hand et al) if you consider the
order of the
1999 Jun 28
0
Resources for teaching R
Greetings!
Soon I will begin teaching 2 courses two students who have never met R or
SPLUS before. I'm just wondering if list members are aware of any on-line
lecture notes about R or using R to teach statistics apart from the
Venables & Smith notes?
One drawback to R is its name, which is not very useful as a search string
in internet search engines!
Murray Jorgensen, Department of
2001 Mar 07
1
Windows: updating to R 1.2.2
Forgive me, but while I find the documentation for initially installing R
to be clear, I'm not so happy about updating.
I want to update from R 1.2.1 to R 1.2.2 (mainly so I can get the debugged
version of pictex() ).
Now I have downloaded the base zip files, say to Z:\Program Files and my
existing installation of R 1.2.1 is sitting in
Z:\Program Files\rw1021.
Running rwinst.exe I need to
2006 Jul 21
0
[Fwd: Re: Parameterization puzzle]
Bother! This cold has made me accident-prone. I meant to hit Reply-all.
Clarification below.
-------- Original Message --------
Subject: Re: [R] Parameterization puzzle
Date: Fri, 21 Jul 2006 19:10:03 +1200
From: Murray Jorgensen <maj at waikato.ac.nz>
To: Prof Brian Ripley <ripley at stats.ox.ac.uk>
References: <44C063E5.3020703 at waikato.ac.nz>
2006 Jun 05
1
Extracting Variance components
I can ask my question using and example from Chapter 1 of Pinheiro & Bates.
> # 1.4 An Analysis of Covariance Model
>
> OrthoFem <- Orthodont[ Orthodont$Sex == "Female", ]
> fm1OrthF <-
+ lme( distance ~ age, data = OrthoFem, random = ~ 1 | Subject )
> summary( fm1OrthF )
Linear mixed-effects model fit by REML
Data: OrthoFem
AIC BIC
2003 Jan 12
1
likelihood and score interval estimates for glms
G'day list!
I'm thinking about programming likelihood and score intervals for
generalized linear models in R based on the paper "On the computation of
likelihood ratio and score test based confidence intervals in
generalized linear models" by Juha Alho (1992) (Statistics in Medicine,
11, 923-930).
Being lazy, I thought that I would ask if anyone else on the list has
2008 Mar 02
2
Recommended Packages
Having just update to R 2.6.2 on my old Windows laptop I notice that the
number of packages is growing exponentially and my usual approach of
get-em-all may not be viable much longer. Has any thought been given to
dividing "contributed" binaries into a recommended set, perhaps a couple
of hundred, and the remained. That way one could install the recommended
ones routinely and add in
2003 Sep 17
5
Quit asking me if I want to save the workspace!
How do you stop R from putting up a dialog box when you quit Rgui?
(I use Windows and I never save workspaces that way)
Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz Fax 7 838 4155
Phone +64 7 838 4773 wk +64 7 849 6486 home
2003 Sep 23
2
R-project [.com?] [.net?]
I got a shock a few days ago when I accidentally visited
www.r-project.com . I thought that the r-project site had been hacked
until I realised my mistake. There is also a site www.r-project.net.
Both of these sites appear to be Japanese. Does anyone know anything
about them? I suppose that it is not unusual for names close to those of
popular sites to be used. It is good that they use a
2006 Nov 13
2
A printing "macro"
I am exploring the result of clustering a large multivariate data set
into a number of groups, represented, say, by a factor G.
I wrote a function to see how categorical variables vary between groups:
> ddisp <- function(dvar) {
+ csqt <- chisq.test(G,dvar)
+ print(csqt$statistic)
+ print(csqt$observed)
+ print(round(csqt$expected))
+ round(csqt$residuals)
+ }
>
> x
2001 Sep 18
2
Error mean square
If rb.lm is an lm-object, I can access the error mean square as
s2 <- sum(rb.lm$residuals^2)/rb.lm$df.residual
This seems a bit like hard work for such a commonly wanted quantity. Is
there a better way to do this?
Murray Jorgensen
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at
2002 Dec 03
2
Array multiplication
I wanted a sort of matrix product of an array and a matrix.
As there does not seem to be any array multiplication apart from outer()
I proceeded as follows:
lambda <- array(0, c(n,m,d))
# stuff omitted
# zed is an n by m matrix
#
# \lamb.star_{ik}
lamb.star <- matrix(0, nrow=n, ncol=d)
for (i in 1:n) {
for (k in 1:d) {
for (j in 1:m) {
lamb.star[i,k] = lamb.star[i,k] +
2000 Oct 11
0
Balanced incomplete block analysis
At 07:12 AM 10-10-00 +0100, Prof Brian D Ripley wrote:
>On Tue, 10 Oct 2000, Murray Jorgensen wrote:
>
>> Excuse me everyone, but I don't have to teach this very often!
>>
>> Has anyone got some R code for doing adjusted treatment means and the
>> recovery of inter-block information in the analysis of balanced incomplete
>> block designs?
>
>Do you
2003 Aug 20
5
Interlacing two vectors
I want to interlace two vectors. This I can do:
> x <- 1:4
> z <- x+0.5
> as.vector(t(cbind(x,z)))
[1] 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
but this seems rather inelegant. Any suggestions?
Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz
2002 Oct 28
2
Combining simulation results
In one saved workspace I have the results of a simulation experiment stored
as an array "resarray".
> dim(resarray)
[1] 10 6 500 3
In another workspace I have a similar array from another run of the
simulation.
I want to combine the two arrays into a single array of dimensions
10, 6, 1000, 3
What's the best way to do this?
Murray Jorgensen
Dr Murray Jorgensen
2008 Oct 11
1
step() and stepAIC()
The birth weight example from ?stepAIC in package MASS runs well as
indeed it should.
However when I change stepAIC() calls to step() calls I get warning
messages that I don't understand, although the output is similar.
Warning messages:
1: In model.response(m, "numeric") :
using type="numeric" with a factor response will be ignored
(and three more the same.)
Checked
2006 May 02
0
Pasting data into scan() - oops!
I forgot to mention that I am using Windows XP.
-------- Original Message --------
Subject: Pasting data into scan()
Date: Tue, 02 May 2006 11:55:03 +1200
From: Murray Jorgensen <maj at stats.waikato.ac.nz>
To: r-help at stat.math.ethz.ch
The file TENSILE.DAT from the Hand et al "Handbook of Small Data Sets"
looks like this:
[...]
--
Dr Murray Jorgensen