Displaying 20 results from an estimated 2000 matches similar to: "VarCorr procedure from lme4"
2011 Jan 19
2
VarCorr
I have a loop that I would like to use to extract the "stddev" for
each itteration so I can average the "stddev" for all the runs. It
would be helpful to know how to extract the "stddev" for each run from
the VarCorr. Thanks
MCruns<-1000
sighatlvec<-rep(NA,MCruns)
sighatbvec<-rep(NA,MCruns)
sighatevec<-rep(NA,MCruns)
for(mc in 1:MCruns)
{
2005 Sep 01
2
VarCorr function for assigning random effects: was Question
If you are indeed using lme and not lmer then the needed function is
VarCorr(). However, 2 recommendations. First, this is a busy list and
better emails subject headers get better attention. Second, I would
recommend using lmer as it is much faster. However, VarCorr seems to be
incompatible with lmer and I do not know of another function to work
with lmer.
Hence, a better email subject header
2005 Jan 11
1
lme4 print and summary errror
Hi all - (this is posted to r-help and R-SIG-MAC)
OSX 10.3.7, R 2.0.1, lme4/Matrix/latticeExtra latest, fresh install of
R. MASS loaded (or not).
I am getting an error message for the print() and summary() commands
with all lme models I try and run in lme4 (GLMM's work fine). Using
the example from the lme help, summary and print produce the following
errors, despite the model being
2005 May 09
1
bootstap and lme4
Hi,
I am trying to get bootstrap confidence intervals on variance
components and related statistics. To calculate the variance components
I use the package lme4.
> off.fun <- function(data, i){
d <- data[i,]
lme1<- lmer(y ~ trt + (trt-1|group), d)
VarCorr(lme1)@reSumry$group[2,1] #just as an example
}
> off.boot <- boot(data=data.sim, statistic=off.fun, R=100)
If
2005 Jun 24
1
lme4 extracting individual variance components
Hi,
For further calculations I need to extract indivdual Variances of
different random effects from a fitted model.
I found out how to extract the correlations
(VarCorr(m1)@reSumry$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!
2011 Jun 08
1
using stimulate(model) for parametric bootstrapping in lmer repeatabilities
Hi all,
I am currently doing a consistency analysis using an lmer model and
trying to use parametric bootstrapping for the confidence intervals.
My model is like this:
model<-lmer(y~A+B+(1|C/D)+(1|E),binomial)
where E is the individual level for consistency analysis, A-D are
other fixed and random effects that I have to control for.
Following Nakagawa and Scheilzeth I can work out the
2008 Feb 05
1
Extracting level-1 variance from lmer()
All,
How does one extract the level-1 variance from a model fit via lmer()?
In the code below the level-2 variance component may be obtained via
subscripting, but what about the level-1 variance, viz., the 3.215072 term?
(actually this term squared) Didn't see anything in the archives on this.
Cheers,
David
> fm <- lmer( dv ~ time.num*drug + (1 | Patient.new), data=dat.new )
2012 Oct 13
2
Function hatTrace in package lme4
Dear all,
For a project I need to calculate the conditional AIC of a mixed effects
model.
Luckily, I found a reference in the R help forum for a function to be used:
CAIC <- function(model) {
sigma <- attr(VarCorr(model), 'sc')
observed <- attr(model, 'y')
predicted <- fitted(model)
cond.loglik <- sum(dnorm(observed,
2003 Jul 14
1
methods help and glmmPQL
Dear All,
I would like to ask you to help me with my memeory. I remember using some
function that would list all the possible methods I could apply to an
object. Say, if I had an object of
class=lme,
it would tell me that that I could do stuff like
qqnorm(myobjct), or VarCorr(myobject). In general, a very complete list.
I though this list of all possible methods would pop out by typing
2004 Sep 21
2
Bootstrap ICC estimate with nested data
I would appreciate some thoughts on using the bootstrap functions in the
library "bootstrap" to estimate confidence intervals of ICC values
calculated in lme.
In lme, the ICC is calculated as tau/(tau+sigma-squared). So, for instance
the ICC in the following example is 0.116:
> tmod<-lme(CINISMO~1,random=~1|IDGRUP,data=TDAT)
> VarCorr(tmod)
IDGRUP = pdLogChol(1)
2006 Oct 04
1
extracting nested variances from lme4 model
I have a model:
mod1<-lmer( x ~ (1|rtr)+ trth/(1|cs) , data=dtf) #
Here, cs and rtr are crossed random effects.
cs 1-5 are of type TRUE, cs 6-10 are of type FALSE,
so cs is nested in trth, which is fixed.
So for cs I should get a fit for 1-5 and 6-10.
This appears to be the case from the random effects:
> mean( ranef(mod1)$cs[[1]][1:5] )
[1] -2.498002e-16
> var(
2006 Sep 04
1
Problem with Variance Components (and general glmm confusion)
Dear list,
I am having some problems with extracting Variance Components from a random-effects model:
I am running a simple random-effects model using lme:
model<-lme(y~1,random=~1|groupA/groupB)
which returns the output for the StdDev of the Random effects, and model AIC etc as expected.
Until yesterday I was using R v. 2.0, and had no problem in calling the variance components of the
2007 Nov 09
1
Confidence Intervals for Random Effect BLUP's
I want to compute confidence intervals for the random effect estimates
for each subject. From checking on postings, this is what I cobbled
together using Orthodont data.frame as an example. There was some
discussion of how to properly access lmer slots and bVar, but I'm not
sure I understood. Is the approach shown below correct?
Rick B.
# Orthodont is from nlme (can't have both nlme and
2013 Sep 12
1
Importing packages in Depend
Hi,
I am currently preparing a new version of my package papeR. When I run R CMD
check using the development version of R I get the following note:
Package in Depends field not imported from: ?nlme?, ?lme4?, ?survival?
These packages needs to imported from for the case when
this namespace is loaded but not attached.
I now have problems to fix this issue. It is easy to get rid of two of the
2006 May 08
1
Repeatability and lme
Dear R-help list members
I gathered longitudinal data on fish behaviour which I try to analyse using
a multi level model for change. Mostly, I am following Singer & Willett
(2003), who provide also the S/R code for their examples in the book (e.g.
http://www.ats.ucla.edu/stat/Splus/examples/alda/ch4.htm). Of course I am
interested in change over time, but I am also very much interested in
2007 Jan 02
1
How to extract the variance componets from lme
Here is a piece of code fitting a model to a (part) of a dataset, just
for
illustration. I can extract the random interaction and the residual
variance
in group meth==1 using VarCorr, but how do I get the other residual
variance?
Is there any way to get the other variances in numerical form directly -
it
seems a litte contraintuitive to use "as.numeric" when extracting
estimates,
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).
2005 Oct 10
1
lmer / variance-covariance matrix random effects
Hello,
has someone written by chance a function to extract the
variance-covariance matrix from a lmer-object? I've noticed the VarCorr
function, but it gives unhandy output.
Regards,
Roel de Jong
2006 Feb 20
1
Extracting variance components from lmer
Hi All.
I need a bit of help extracting the residual error variance from the VarCorr
structure from lmer.
#Here's a 2-way random effects model
lmer.1 <- lmer(rating ~ (1|person)+(1|rater), data = dat)
#Get the structure
vc.fit <- VarCorr(lmer.1)
#results in.....
$person
1 x 1 Matrix of class "dpoMatrix"
(Intercept)
(Intercept) 0.7755392
$rater
1 x 1 Matrix
2006 Oct 08
1
Simulate p-value in lme4
Dear r-helpers,
Spencer Graves and Manual Morales proposed the following methods to
simulate p-values in lme4:
************preliminary************
require(lme4)
require(MASS)
summary(glm(y ~ lbase*trt + lage + V4, family = poisson, data =
epil), cor = FALSE)
epil2 <- epil[epil$period == 1, ]
epil2["period"] <- rep(0, 59); epil2["y"] <- epil2["base"]