Displaying 20 results from an estimated 3000 matches similar to: "Simulate p-value in lme4"
2006 Oct 08
1
Simulate p-value in lme4
Dear r-helpers,
Spencer Graves and Manual Morales proposed the following methods to
simulate p-values in lme4:
************preliminary************
require(lme4)
require(MASS)
summary(glm(y ~ lbase*trt + lage + V4, family = poisson, data =
epil), cor = FALSE)
epil2 <- epil[epil$period == 1, ]
epil2["period"] <- rep(0, 59); epil2["y"] <- epil2["base"]
2006 Dec 19
2
Problem with glmmADMB
library(glmmADMB)
#Example for glmm.admb
data(epil2)
glmm.admb(y~Base*trt+Age
+Visit,random=~Visit,group="subject",data=epil2,family="nbinom")
Gives:
Error in glmm.admb(y ~ Base * trt + Age + Visit, random = ~Visit,
group = "subject", :
The function maximizer failed
******************
R version 2.4.1 RC (2006-12-14 r40181)
powerpc-apple-darwin8.8.0
locale:
C
2011 Nov 10
1
questions about epil repo
hi,
I installed the epil repo and imported the key but everytime i try to
install a package from epil
Public key for proftpd-1.3.3f-1.el6.i686.rpm is not installed
I get this with evry package i try to install
using centos 6 i686
2013 Jun 07
1
Function nlme::lme in Ubuntu (but not Win or OS X): "Non-positive definite approximate variance-covariance"
Dear all,
I am estimating a mixed-model in Ubuntu Raring (13.04¸ amd64), with the
code:
fm0 <- lme(rt ~ run + group * stim * cond,
random=list(
subj=pdSymm(~ 1 + run),
subj=pdSymm(~ 0 + stim)),
data=mydat1)
When I check the approximate variance-covariance matrix, I get:
> fm0$apVar
[1] "Non-positive definite
2005 Mar 23
1
Negative binomial GLMMs in R
Dear R-users,
A recent post (Feb 16) to R-help inquired about fitting
a glmm with a negative binomial distribution.
Professor Ripley responded that this was a difficult problem with the
simpler Poisson model already being a difficult case:
https://stat.ethz.ch/pipermail/r-help/2005-February/064708.html
Since we are developing software for fitting general nonlinear random
effects models we
2006 Dec 19
1
effect plot
Dear R users,
Is there a simple way to use the effect function (library(effects)) with
a GEE estimated model?
library(gee)
library(MASS)
library(effects)
attach(epil)
b = gee(y ~ lbase*trt + lage + V4, family=poisson, id=subject,
corstr="exchangeable")
plot(effect("lbase*trt", b))
# Errore in effect("lbase*trt", b) : nessun metodo applicabile per
2007 May 17
2
How to select specific rows from a data frame based on values
Dear Group:
I am working with a data frame containing 316 rows of individuals
with 79 variables. Each of these 79 variables have values that range
between -4 to +4, and I want to subset this data frame so that in the
resulting new dataframe, values of _all_ of these variables should
range between -3 and +3.
Let's say I have the following dataframe (it's a toy example with 4
individuals
2011 Nov 18
1
[R-sig-ME] account for temporal correlation
[cc'ing back to r-help]
On Fri, Nov 18, 2011 at 4:39 PM, matteo dossena
<matteo.dossena at gmail.com> wrote:
> Thanks a lot,
>
> just to make sure i got it right,
>
> if (using the real dataset) from the LogLikelihood ratio test model1 isn't "better" than model,
> means that temporal auto correlation isn't seriously affecting the model?
yes. (or
2008 Jul 14
0
Question regarding lmer vs glmmPQL vs glmm.admb model on a negative binomial distributed dependent variable
Hi R-users,
I intend to apply a mixed model on a set of longitudinal data, with a negative binomial distributed dependent variable, and after following the discussions on R help list I saw that more experienced people recommended using lmer (from lme4 pack), glmmPQL (from MASS) or glmm.admb (from glmmADMB pack)
My first problem: yesterday this syntax was ok, now I get this weird message (I
2011 Dec 23
1
Long jobs completing without output
I've been running a glmer logit on a very large data set (600k obs).
Running on a 10% subset works correctly, but for the complete data set,
R completes apparently without error, but does not display the results.
Given these jobs take about 200 hours, it's very hard to make progress
by trial and error.
I append the code and the sample and complete output. As is apparent, I
upgraded R
2004 Jan 15
1
nlme vs aov with Error() for an ANCOVA
Hi
I compouted a multiple linear regression with repeated measures on one
explanatory variable:
BOLD peak (blood oxygenation) as dependent variable,
and as independent variables I have:
-age.group (binaray:young(0)/old(1))
-and task-difficulty measured by means of the reaction-time 'rt'. For
'rt' I have repeated measurements, since each subject did 12 different
tasks.
-> so
2007 Apr 13
2
replicates in repeated ANOVA
Hi,
I have sort of a newbie question. I've seriously put a lot of effort into how to handle simple replicates in a repeated ANOVA design, but haven't had much luck.
I really liked reading "Notes on the use of R for psychology experiments and questionnaires", by Jonathan Baron and Yuelin Li ( http://www.psych.upenn.edu/~baron/rpsych/rpsych.html ) but still didn't run across
2006 Feb 24
1
SE of parameter estimates in glmm.admb
Dear R users,
Does anyone know how to get standard errors of the
parameter estimates in glmm.admb?
Thanks,
Istvan
2012 Jun 06
3
Sobel's test for mediation and lme4/nlme
Hello,
Any advice or pointers for implementing Sobel's test for mediation in
2-level model setting? For fitting the hierarchical models, I am using
"lme4" but could also revert to "nlme" since it is a relatively simple
varying intercept model and they yield identical estimates. I apologize for
this is an R question with an embedded statistical question.
I noticed that a
2007 May 13
2
Some questions on repeated measures (M)ANOVA & mixed models with lme4
Dear R Masters,
I'm an anesthesiology resident trying to make his way through basic
statistics. Recently I have been confronted with longitudinal data in
a treatment vs. control analysis. My dataframe is in the form of:
subj | group | baseline | time | outcome (long)
or
subj | group | baseline | time1 |...| time6 | (wide)
The measured variable is a continuous one. The null hypothesis in
2008 Dec 05
1
lme4, error in mer_finalize(ans)
Using lmer() on my data results in an error. The problem,
I think, is my model specification. However, lm() works
ok.
I recreated this error with a more simple dataset. (See
code below.)
# word and letter recognition data
# two within factors:
# word length: 4, 5, 6 letters
# letter position: 1-4 (in 4-letter words), 1-5 (in
5-letter words), 1-6 (in 6-letter words)
# one dependent variable:
#
2010 Oct 25
2
Mixed-effects model for overdispersed count data?
Hi,
I have to analyse the number of provisioning trips to nestlings according to a number of biological and environmental factors. I was thinking of building a mixed-effects model with species and nestid as random effects, using a Poisson distribution, but the data are overdispersed (variance/mean = 5). I then thought of using a mixed-effects model with negative binomial distribution, but I have
2003 Apr 09
1
'Apparently' trouble with name spaces and Sweave...
Ben Bolstad experienced something odd while running R CMD check over
a package of ours using r-devel (yesterday's fresh).
He tracked down the problem to a vignette calling 'library(MASS)'.
Please kindly ignore if this is a known (and temporary) issue.
Laurent
----- Forwarded message from Ben Bolstad <bolstad@stat.berkeley.edu> -----
Return-Path:
2017 Dec 26
1
identifying convergence or non-convergence of mixed-effects regression model in lme4 from model output
Hi R community!
I've fitted three mixed-effects regression models to a thousand
bootstrap samples (case-resampling regression) using the lme4 package in
a custom-built for-loop. The only output I saved were the inferential
statistics for my fixed and random effects. I did not save any output
related to the performance to the machine learning algorithm used to fit
the models (REML=FALSE).
2011 Apr 04
0
[R-sig-ME] Documentation for the glm module in jags/rjags?
It turns out that when I use GUI (file-change dir) to set the working
directory, R will crash.
If I use setwd() instead, the example runs well.
Regards,
On 4 April 2011 00:17, Wincent <ronggui.huang@gmail.com> wrote:
> OK, I dig into the problem and found that Chinese character in the path
> should be blamed.
> Once the path rename to English only, it works.
>
> Regards,