Displaying 20 results from an estimated 800 matches similar to: "GLM Logit and coefficient testing (linear combination)"
2006 May 08
1
Panel Data Estimators (within, between, Random Effects estimator)
Dear R Users,
Here is another probelm/question.
I would like to run some panel regressions with R. Therefore I have
combined several time periods of data for different individuals in my
database.
I have already run pooled OLS but I would need to calculate a Fixed
Effects Estimator (within estimator). Unfortunately I couldn't find
anything like that in the RSearch and I suppose that lme
2004 Feb 01
2
3 little questions
> From: Siegfried.Macho
>
> Dear R-helpers,
>
> 3 questions:
> 1. Is there a package that contains a routine for computing
> Kendall's W
> (coefficient of concordance), with and without ties ?
Is that the same as Kendall's tau, as in cor(..., method="kendall")?
> 2. Is there a package that contains a routine for computing
> Goodman' s
2004 Jan 23
1
Problem with hasArg() using R-files
Please do give reproducible example. The code you gave, which you claimed
`works correctly' doesn't:
> SDT.Optim <- function(crit = NULL, Hess = F)
+ {
+ q <- length(par); x <- data
+ if(hasArg(crit))
+ cat("\n Crit present\n")
+ else
+
2010 Aug 05
0
multiple comparisons after glm
Dear list members,
I have a question concerning multiple comparisons after using glm.
My response variable is days until emergence of an insect species. The explanatory variables are sex (two levels), parasitoids added (two levels) and populations (34 levels). I would like to know now which populations are different in days until insect emergence.
For this I used multiple comparisons as
2005 Feb 25
0
Problem using stepAIC/addterm (MASS package)
Hello,
I'm currently dealing with a rather strange problem when using the
function "stepAIC" ("MASS" package). The setting is the following: From
model learning data sets ("learndata"), I want to be able to build
prediction functions (in order to save them in a file for further use).
This is done by the function "pred.function" (see below). Therein,
2003 Nov 28
1
problem with nls()
I wanted to use the nls() module to solve a Problem from Sen & Srivastava
(1990, p.209). Here is the (basic) code used to perform the estimation:
library(SenSrivastava)
library(nls)
data(E9.8)
# Use Linear Least Square for estimating start values
lm.obj <- lm(R.1 ~ I.1 + S.1, data = E9.8)
nls1.obj <- nls(R.1 ~ b.0 + b.1*(I.1^a.1-1)/a.1 + b.2*(S.1^a.2-1)/a.2,
2011 Mar 14
1
Javascript & Rails future
Hi,
David H.H. announced recently that jquery is going to be the default in Rails 3.1, and that Prototype helpers / RJS are going into a gem.
What does that mean for the future? Should we progressively forget about things like javascript helpers, RJS, and all these fun parts of rails? And start coding with jquery/json in mind?
I''m not against that at all, but I have to admit I find RJS
2010 Mar 17
2
Is samba right for me?
I am currently a college student looking for ways to prepare myself for any
Server Administration job once I get out of college.
I've been going back and worth between Freenode IRC channels (#linux and
##windows) trying to decide what to learn.
On one hand, we have Windows Server 2008 R2, people in #linux keep on
telling me to just go ahead and use it because "samba can't provide
2004 Dec 02
3
Dominant factors in aov?
Hi all,
I'm using R 2.0.1. for Windows to analyze the influence of following factors
on response Y:
A (four levels)
B (three levels)
C (two levels)
D (29 levels) with
E (four replicates)
The dataset looks like this:
A B C D E Y
0 1 1 1 1 491.9
0 1 1 1 2 618.7
0 1 1 1 3 448.2
0 1 1 1 4 632.9
250 1 1 1 1 92.4
250 1 1 1 2 117
250 1 1 1 3 35.5
250 1 1 1 4 102.7
500 1 1 1 1 47
500 1 1 1 2 57.4
2008 Nov 27
1
lmer refuses nested random factors
I am trying to run the following model in R
> lmer(leaves.eaten~Geocytotype+(1|TEST/
PLANT),data=cyphoplantfeeding,family=poisson)
My experimental setup is 41 replicates (TEST) of an experiment in
which there are three Geocytotypes of a plant species in each TEST,
and two plant pseudoreplicates per Geocytotype in each test (i.e.
3*2=6 plants per test). So my random factors are trying
2005 May 23
0
using lme in csimtest
Hi group,
I'm trying to do a Tukey test to compare the means of a factor
("treatment") with three levels in an lme model that also contains the
factors "site" and "time":
model = response ~ treatment * (site + time)
When I enter this model in csimtest, it takes all but the main factor
"treatment" as covariables, not as factors (see below).
Is it
2012 Sep 07
3
Problem with duplicates in row.names
Hello,
I am drawing a heatmap with hundreds of genes. Everything work fine, except when I want to had the name of the genes as the row.names with
>row.names (a)<-a$Name
And there''s this things that duplicate are not allowed...
How can I do to allow duplicates ??? I don''t have the choice I can''t just have numbers .
Thanks for your help, I am new in R ...
Fred
2009 Mar 03
2
R - MATLAB apply like function
Dear all,
I very often use the R function "apply", for speedup purposes. I am now also using MATLAB, and would like to use the same kind of function.
I have already asked MATLAB people, and the answer is : "vectorize"... but of course, this is not always possible. So, instead of using
a FOR loop all the time, I tried using the bsxfun. So you R people, who might also use MATLAB,
2006 Jan 10
2
Obtaining the adjusted r-square given the regression coefficients
Hi people,
I want to obtain the adjusted r-square given a set of coefficients (without the intercept), and I don't know if there is a function that does it. Exist????????????????
I know that if you make a linear regression, you enter the dataset and have in "summary" the adjusted r-square. But this is calculated using the coefficients that R obtained,and I want other coefficients
2012 Sep 09
3
how to save a heatmap.2 in png /jpeg /tiff
Hey, I am still working on my heat map (for those who are read my previous post about row.names)…
Now, I would like to save my heat map.2 in .png or .tiff in order being able to work on the picture in photoshop, but it doesn't work.
I'am using (as I have found on some forum)
> png("heatmap.2.png) # and it just doesn't work. when I try doing it with::
2004 Feb 16
1
nlme_crossed AND nested random effects
Dear R-help group,
How can I define a lme with 3 factors(a,b,c), where c is nested in b,
and a is crossed with b/c?
I think that:
lme(response ~ ..., data = Data,
random = pdBlocked(list(pdIdent(~ a - 1), pdIdent(~ b - 1))))
is one part of the answer and:
lme(response~..., data=Data, random=~1|b/c)
is the other part of the answer but how can I combine them??
Could anybody please help
2024 Mar 22
1
Problem with new version of R: Mutated vocals
Dear ladies and gentlemen,
I have recently installed the latest version of R (4.3.3) for windows. Now I have the following problems with mutated vowels like ?, ?, etc. Here is an example:
If I type the command:
Dir <- "C/Users/macho/Documents/_LVn/Experimentelle ?bungen"
in the R console there is no problem. However, if I put the same command into a source file (e.g. Test.r) and call
2008 Apr 22
2
optimization and gradient
Dear all,
I am using the functions 'optim' and 'nlminb'. For both, you can provide
a function which computes the gradient of the objective function (to
enhance speed and precision). In my case, both the objective function
and the gradient take time to be computed and share many common
computations (similar matrix, products, etc...). Therefore, I have to
compute these
2010 Feb 08
0
Mixed logit models with a random coefficient
Hi All,
Sorry to bother you. I'm trying to estimate a set of discrete choice
data in R with mixed logit models where one coefficient is random and
normally distributed. I've searched on the R help archive and don't see much
information very specific to what I'm doing, so I write the code myself,
which involves simulated maximum likelihood. But it doesn't work, as I
compare
2005 Jun 24
1
lme4 extracting individual variance components
Hi,
For further calculations I need to extract indivdual Variances of
different random effects from a fitted model.
I found out how to extract the correlations
(VarCorr(m1)@reSumry$group1) but I was not able to find a way to
extract the other components individually.
To extract the Residuals I tried: (ranef(m1)@ stdErr) which
unfortunately did not work.
Thank you very much for your help!