Displaying 20 results from an estimated 4000 matches similar to: "Loop elimination question"
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>
2004 May 24
2
Month names
This is how I get the month names from within R:
> mon <- rep(strptime("01/01/1952", format = "%d/%m/%Y"), 12)
> mon$mon <- mon$mon + 0:11
> mnam <- months(mon, abbreviate = F)
> mnam
[1] "januar" "februar" "marts" "april" "maj" "juni"
"juli" "august"
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
1999 Jul 16
0
Randomization tests
Please excuse this request from a beginner.
I'm teaching an introductory module on experimental design and I want to
illustrate the idea of tests based on the randomization distribution.
If anyone has written any R code to do a randomization test in a particular
example I'd be very grateful if you could show me your code.
Murray Jorgensen
Murray Jorgensen, Department of Statistics,
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
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
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$Sex == "Female", ]
> fm1OrthF <-
+ lme( distance ~ age, data = OrthoFem, random = ~ 1 | Subject )
> summary( fm1OrthF )
Linear mixed-effects model fit by REML
Data: OrthoFem
AIC BIC
2008 Mar 02
2
Recommended Packages
Having just update to R 2.6.2 on my old Windows laptop I notice that the
number of packages is growing exponentially and my usual approach of
get-em-all may not be viable much longer. Has any thought been given to
dividing "contributed" binaries into a recommended set, perhaps a couple
of hundred, and the remained. That way one could install the recommended
ones routinely and add in
2002 Oct 28
2
Combining simulation results
In one saved workspace I have the results of a simulation experiment stored
as an array "resarray".
> dim(resarray)
[1] 10 6 500 3
In another workspace I have a similar array from another run of the
simulation.
I want to combine the two arrays into a single array of dimensions
10, 6, 1000, 3
What's the best way to do this?
Murray Jorgensen
Dr Murray Jorgensen
2006 Nov 13
2
A printing "macro"
I am exploring the result of clustering a large multivariate data set
into a number of groups, represented, say, by a factor G.
I wrote a function to see how categorical variables vary between groups:
> ddisp <- function(dvar) {
+ csqt <- chisq.test(G,dvar)
+ print(csqt$statistic)
+ print(csqt$observed)
+ print(round(csqt$expected))
+ round(csqt$residuals)
+ }
>
> x
2003 Sep 17
5
Quit asking me if I want to save the workspace!
How do you stop R from putting up a dialog box when you quit Rgui?
(I use Windows and I never save workspaces that way)
Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz Fax 7 838 4155
Phone +64 7 838 4773 wk +64 7 849 6486 home
2006 May 02
0
Pasting data into scan() - oops!
I forgot to mention that I am using Windows XP.
-------- Original Message --------
Subject: Pasting data into scan()
Date: Tue, 02 May 2006 11:55:03 +1200
From: Murray Jorgensen <maj at stats.waikato.ac.nz>
To: r-help at stat.math.ethz.ch
The file TENSILE.DAT from the Hand et al "Handbook of Small Data Sets"
looks like this:
[...]
--
Dr Murray Jorgensen
2001 Sep 18
2
Error mean square
If rb.lm is an lm-object, I can access the error mean square as
s2 <- sum(rb.lm$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
2005 Sep 08
1
Coarsening Factors
It is not uncommon to want to coarsen a factor by grouping levels
together. I have found one way to do this in R:
> sites
[1] F A A D A A B F C F A D E E D C F A E D F C E D E F F D B C
Levels: A B C D E F
> regions <- list(I = c("A","B","C"), II = "D", III = c("E","F"))
> library(Epi)
> region <-
2009 Nov 25
2
R or C++ on FreeNX servers
Hi all,
I have just found out that the machine learning group in our Faculty has
a lot of spare capacity on their FreeNX servers. I do not know a lot
about these beasts but I understand that they are a free version of
something produced by a firm called "NoMachine".
They are designed for executing parallel algorithms and I thought that
they might be of use in a project of mine
2010 Jun 14
2
Html help
I have just installed R 2.11.1 on my XP laptop.
I like html help for browsing but text help for on-the-fly look-ups. I
was a bit surprised when I was asked to choose between them during the
installation. I chose text, thinking I could fix the html help later,
which is what I am trying to do now.
Now when I ask for html help my browser goes to
'http://-ip-number-/doc/html/index.html'
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
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 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] +