Displaying 20 results from an estimated 1000 matches similar to: "mixed effect-models"
2002 Sep 23
2
R crash with internet2.dll
Hi,
I'm using:
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
status
major 1
minor 5.1
year 2002
month 06
day 17
language R
and I would like to apply:
> update.packages()
trying URL
2000 Sep 12
1
HLM in R
Does anyone know of code to conduct hierarchical (that is, multi-level)
models using R. Beyond simply requiring a nested design, I want to model
explicitly the covariance between levels as is done in such multi-level
modeling software as HLM or MLwin and discussed in Goldestein (1999)
available online at http://www.arnoldpublishers.com/support/goldstein.htm (a
nice and free resource for anyone
2009 Feb 28
1
lme4 and Variable level detection
I am making a little GUI for lme4, and I was wondering if there is a function
that automatically detects on which level every variable exists.
Furtheremore I got kind of confused about what a random effects model
actually calculates.
I have some experience with commercial software packages for multilevel
analysis, like HLM6, and I was surprised that lme4 does not require the user
to specify the
2003 Jul 03
2
Bug in plotting groupedData-objects
Dear Experts,
May be the problem is still solved, however I tried to find the answer in
the archives:
I use:
> R.version
_
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
status
major 1
minor 7.1
year 2003
month 06
day 16
2002 Nov 07
4
Preferable contrasts?
Dear all,
I'm working with Cox-regression, because data could be censored.
But in this particular case not.
Now I have a simple example: PRO and PRE are (0,1) coded.
The response is not normal distributed.
We are interested in a model which could describe interaction.
But my results are depending strongly in the choose of the contrast option.
It is clear that there is some dependence in
2002 Oct 09
3
proc mixed vs. lme
Dear All,
Comparing linear mixed effect models in SAS and R, I found the following
discrepancy:
SAS R
random statement random subj(program); random = ~ 1 |
Subj
-2*loglik 1420.8 1439.363
random effects
variance(Intercept) 9.6033 9.604662
2002 Oct 09
3
Summary: proc mixed vs. lme
Summary: proc mixed vs. lme
The objective of this summary is to help people
to get more familiar with the specification of
random effects with proc mixed or lme.
Very useful are the examples of Ramon Littell's book:
"SAS System for Mixed Models (1996)"
(http://ftp.sas.com/samples/A55235)
The same data set's are kindly made available
by Douglas Bates in the
2004 Sep 12
1
Discrepency between R and MlwiN
When playing around fitting unconditional growth models using R and MlwiN today, I produced two different sets of estimates that I can't reconcile and wondered if anyone here has an idea:
The data is two-level repeated measures data with measures nested within child. There are two measures per child. I've fit an unconditional growth model as in Singer and Willet (2003) that allows for
2005 Aug 05
3
Help, my RGui is speaking French!
Dear R-helpers,
First of all I have nothing against the French language!
But now my problem, yesterday I installed R 2.1.1
and I had to experience that my RGui is speaking French.
My windows locals is French (Switzerland).
I'm used to English and I want to reset my RGui to English.
I was seeking for the solution in the archives,
however not successfully.
By the way the searchable archives
2008 Jun 15
2
R vs SAS and HLM on multilevel analysis- basic question
Hi R users!
I am trying to learn some multilevel analysis, but unfortunately i am now very confused. The reason: http://www.ats.ucla.edu/stat/hlm/seminars/hlm_mlm/mlm_hlm_seminar.htm
http://www.ats.ucla.edu/stat/sas/seminars/sas_mlm/mlm_sas_seminar.htm
and
MlmSoftRev. pdf from mlmRev package.
>From what i see, the first two links seem to declare the level one variable as a random part (i
2002 Apr 01
2
writing a package for generalized linear mixed modesl
Happy new month, everyone!
I am planning to write a NIH grant proposal to study ways to speed
Monte Carlo based maximum likelihood algorithm for hierarchical models
with a focus on generalized linear mixed models (GLM with random
effects). I thought it would be nice and also increase the chance of
funding if I could produce an R package in the process. I understand
that Prof. Pinheiro ang Bates
2006 Jul 24
3
standardized random effects with ranef.lme()
Using ranef() (package nlme, version 3.1-75) with an 'lme' object I can
obtain random effects for intercept and slope of a certain level (say:
1) - this corresponds to (say level 1) "residuals" in MLWin. Maybe I'm
mistaken here, but the results are identical.
However, if I try to get the standardized random effects adding the
paramter "standard=T" to the
2003 Dec 19
1
problem with rm.impute of the Design library
Hello,
I'm using:
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
status
major 1
minor 8.1
year 2003
month 11
day 21
language R
and I get the following error with:
library(Design)
df <- list(pre=c(0,, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1,
2005 Oct 07
3
Converting PROC NLMIXED code to NLME
Hi,
I am trying to convert the following NLMIXED code to NLME, but am
running into problems concerning 'Singularity in backsolve'. As I am new
to R/S-Plus, I thought I may be missing something in the NLME code.
NLMIXED
***********
proc nlmixed data=kidney.kidney;
parms delta=0.03 gamma=1.1 b1=-0.003 b2=-1.2 b3=0.09 b4=0.35 b5=-1.43
varu=0.5;
eta=b1*age+b2*sex+b3*gn+b4*an+b5*pkn+u;
2003 Sep 04
7
Comparison of SAS & R/Splus
I am one of only 5 or 6 people in my organization making the
effort to include R/Splus as an analysis tool in everyday work -
the rest of my colleagues use SAS exclusively.
Today, one of them made the assertion that he believes the
numerical algorithms in SAS are superior to those in Splus
and R -- ie, optimization routines are faster in SAS, the SAS
Institute has teams of excellent numerical
2007 May 08
3
ordered logistic regression with random effects. Howto?
I'd like to estimate an ordinal logistic regression with a random
effect for a grouping variable. I do not find a pre-packaged
algorithm for this. I've found methods glmmML (package: glmmML) and
lmer (package: lme4) both work fine with dichotomous dependent
variables. I'd like a model similar to polr (package: MASS) or lrm
(package: Design) that allows random effects.
I was
2005 Aug 17
1
two-level poisson, again
Hi,
I compare results of a simple two-level poisson estimated using lmer
and those estimated using MLwiN and Stata (v.9).
In R, I trype:
-------------------------------------------------------------------------------------------
m2 <- lmer(.D ~ offset(log(.Y)) + (1|pcid2) + educy + agri, male, poisson)
-------------------------------------------------------------------------------------------
2010 Sep 24
1
Fitting GLMM models with glmer
Hi everybody:
I?m trying to rewrite some routines originally written for SAS?s PROC
NLMIXED into LME4's glmer.
These examples came from a paper by Nelson et al. (Use of the
Probability Integral Transformation to Fit Nonlinear Mixed-Models
with Nonnormal Random Effects - 2006). Firstly the authors fit a
Poisson model with canonical link and a single normal random effect
bi ~ N(0;Sigma^2).The
2003 Sep 12
2
partial mantel
Dear all,
Has anyone written R code for partial Mantel Tests- as described for
instance in Legtendre & Legendre (1998) ?
In other words, in a community ecology analysis, I would like to calculate
the correlation between two dissimilarity matrices, controlling for a third
distance matrix representing geographical distances between sites.
Thanks!
Christophe Bouget
Biodiversité et gestion des
2011 Mar 10
1
PROC NLMIXED what package equivalent in R?
To account for likely differences between
families in naturalization rates, we fitted a
generalized linear mixed model, using
PROC NLMIXED in SAS10, with the
naturalization rate per genus (that is, the
number of naturalized species in a genus as
a proportion of the total number of introduced
species in a genus) as the response
variable, a variable coding genera as containing
at least one native