search for: varcorr

Displaying 20 results from an estimated 106 matches for "varcorr".

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...
2012 May 01
1
VarCorr procedure from lme4
Folks In trying to use lmer for a hierarchical model, I encountered the following message: Error in UseMethod("VarCorr") : no applicable method for 'VarCorr' applied to an object of class "mer" foo.mer <- lmer(y ~ TP + (TP|M),data=joe.q) > head(joe.q[,1:5]) TP M AB Trt y 1 1 Jan A NN 19.20002 2 1 Jan A NN 19.06378 3 1 Jan A NN 21.36292 4 1 Jan A NN 16.85191...
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) { samples<-(sqrt(sigbsq)*rnorm(6)) labs<-(sqrt(siglsq)*rnorm(2)) errors<-(sqrt(sigesq)*rnorm(24)) y<-errors+samples[sampfac]+labs[labfac] lmer<-lme...
2011 Jun 08
1
using stimulate(model) for parametric bootstrapping in lmer repeatabilities
...) 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 repeatability estimate using the following (as it is a binomial and the residual variance is fixed at 1). attr(lme4::VarCorr(model)$E, "stddev")^2 / (1*(pi^2)/3 + attr(lme4::VarCorr(model)$E, "stddev")^2 + attr(lme4::VarCorr(model)$C, "stddev")^2 + attr(lme4::VarCorr(model)$D, "stddev")^2 ) My question is can I use stimulate(model) to generate values that I can then use to do p...
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 methods(class = lme) or, methods(class = whatever class my object is), but, if I type: methods(class = lme), I get: "anova.lme" "plot.lme" "simulate.l...
2013 Sep 12
1
Importing packages in Depend
...s namespace is loaded but not attached. I now have problems to fix this issue. It is easy to get rid of two of the three package warnings by using import(lme4) import(survival) in my NAMESPACE. Yet, I cannot import nlme as I then get the following warnings: Warning: replacing previous import ?VarCorr? when loading ?lme4? Warning: replacing previous import ?lmList? when loading ?lme4? I know that nlme is imported in lme4 but I cannot import both at the same time. Can anyone help me here? I do *not* want or can use importFrom as I rely on multiple functions and also rely on non-exported methods...
2008 Feb 05
1
Extracting level-1 variance from lmer()
...el-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 ) > VarCorr(fm) $Patient.new 1 x 1 Matrix of class "dpoMatrix" (Intercept) (Intercept) 8.519916 attr(,"sc") scale 3.215072 > VarCorr(fm)[[1]][1] [1] 8.519916 > VarCorr(fm)[[2]][1] Error in VarCorr(fm)[[2]] : subscript out of bounds ########################...
2004 Sep 21
2
Bootstrap ICC estimate with nested data
...trap functions in the library "bootstrap" to estimate confidence intervals of ICC values calculated in lme. In lme, the ICC is calculated as tau/(tau+sigma-squared). So, for instance the ICC in the following example is 0.116: > tmod<-lme(CINISMO~1,random=~1|IDGRUP,data=TDAT) > VarCorr(tmod) IDGRUP = pdLogChol(1) Variance StdDev (Intercept) 0.1829931 0.427777 Residual 1.3907732 1.179310 > 0.18299/(0.18299+1.39077) [1] 0.1162757 Using the bootstrap library, I can set up theta to do the ICC as follows: >theta<-function(x,DATA){tmod<-lme(CINISMO~1,ra...
2005 Oct 10
1
lmer / variance-covariance matrix random effects
Hello, has someone written by chance a function to extract the variance-covariance matrix from a lmer-object? I've noticed the VarCorr function, but it gives unhandy output. Regards, Roel de Jong
2006 Sep 04
1
Problem with Variance Components (and general glmm confusion)
...a simple random-effects model using lme: model<-lme(y~1,random=~1|groupA/groupB) which returns the output for the StdDev of the Random effects, and model AIC etc as expected. Until yesterday I was using R v. 2.0, and had no problem in calling the variance components of the above model using VarCorr(model), together with their 95% confidence intervals using intervals() - although for some response variables a call to intervals() returns the error: Cannot get confidence intervals on var-cov components: Non-positive definite approximate variance-covariance. I have now installed R v. 2.3.1 and...
2007 Nov 09
1
Confidence Intervals for Random Effect BLUP's
...4 loaded at same time!) # OrthoFem<-Orthodont[Orthodont$Sex=="Female",] # http://tolstoy.newcastle.edu.au/R/help/06/03/23758.html library(lme4) fm1OrthF. <- lmer(distance~age+(age|Subject), data=OrthoFem) lmer(distance~age+(age|Subject), data=OrthoFem)@bVar$Subject[2,2,]* (attr(VarCorr(lmer(distance~age+(age| Subject),data=OrthoFem)),"sc")^2)[1] (attr(VarCorr(fm1OrthF.),"sc")^2)[1] fm1.s <- coef(fm1OrthF.)$Subject fm1.s.var <- fm1OrthF. at bVar$Subject*(attr(VarCorr(fm1OrthF.),"sc")^2)[1] fm1.s0.s <- sqrt(fm1.s.var[1,1,]) fm1.s0.a &l...
2004 Dec 31
1
lme: Confusion about Variances
...*beta + error and error = U + W(t) + Z where U is the random intercept (normally distributed), W(t) the stationary Gaussian process and Z also a normally distributed (the residual) rv. Each of these three random variables have a variance which I am not sure to which output in lme they belong to. VarCorr gives the intercept and residual variance which I assume belong to U and Z respectively. The output of lme gives another estimate called "range" which I assume belongs to the parameter estimate needed for the Gaussian correlation. Are my assumptions correct? And where can I get the varia...
2012 May 14
1
Extract Variance Components
...le.com/ANOVA-problem-td4609062.html, but now focussed on the problem of extracting variance components. I have got my mixed effects model now /narrow$line<-as.factor(narrow$line) rg.lmer <- lapply(split(narrow, narrow$gene),function(x)lmer(value~sex+(1|line:sex)+(1|line),data=x)) str(lme4::VarCorr(rg.lmer[[1]])) (rg.lmer[[1]])/ and want the variance components from each model (one per gene) put in to a data frame, this works for one gene: /## SUCCESS! for one gene... alpha<-as.matrix(lme4::VarCorr(rg.lmer[[1]])) beta<-data.frame(c(alpha,attr(alpha,"sc")^2)) colnames(beta)&l...
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, it's a bit like good old days writing SAS-programs that reads the SAS output files...
2006 May 08
1
Repeatability and lme
...thought it would be appropriate to follow this procedure: > library(nlme) > fm1Rail.lme <- lme(travel ~ 1, data = Rail, random = ~ 1 | Rail) > summary(fm1Rail.lme) ... Random effects: Formula: ~1 | Rail (Intercept) Residual StdDev: 24.80547 4.020779 ... > as.numeric(VarCorr(fm1Rail.lme)[1]) / (as.numeric(VarCorr(fm1Rail.lme)[1]) + as.numeric(VarCorr(fm1Rail.lme)[2] )) [1] 0.9743987 This gives a reasonable, high repeatability. First, I would like to know, whether this computation of repeatability is correct, and if so, how I would have to proceed if there was also a v...
2001 Nov 14
2
lme: how to extract the variance components?
Dear all, Here is the question: For example, using the "petrol" data offered with R. pet3.lme<-lme(Y~SG+VP+V10+EP,random=~1|No,data=petrol) pet3.lme$sigma gives the residual StdDev. But I can't figure out how to extract the "(intercept) StdDev", although it is in the print out if I do "summary(pet3.lme)". In
2009 Oct 20
2
Interpretation of VarCorr results
Dear all, I'm working with a model to estimate components of variance by using the lme() function. The model is as the following: model=lme(fixed=X~1+as.factor(station),data=myData,na.action=na.exclude,rand om=~N+1|spliceOrHoming) Where X is the response measured variable, station is treated as fixed effects factor, N is a continuous variable, and spliceOrHoming is a (ordered)
2003 Feb 13
1
fixed and random effects in lme
...rawley's book (page 361 onwards) so I can check what I am doing. I am tryg to reproduce the nested analysis on page 368: model<-aov(Glycogen~Treatment/Rat/Liver + Error(Treatment/Rat/Liver), rats) using lme. The code: model1<- lme(Glycogen~Treatment, random = ~1|Rat/Liver, data=rats) VarCorr(model1) Variance StdDev Rat = pdLogChol(1) (Intercept) 20.6019981 4.538942 Liver = pdLogChol(1) (Intercept) 0.0540623 0.232513 Residual 42.4362241 6.514309 Does NOT give me the same variance componets I find in Crawley's book (page 371 o...
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 $rat...
2011 Dec 30
0
New version of coxme / lmekin
...<2.2 coxme 2.2 lmekin 2.2 ------------------------------------------------------ beta fixef fixef fixef fixef fixef b ranef ranef ---- ranef ranef var(beta) vcov vcov ---- vcov vcov var(b) VarCorr VarCorr ranef VarCorr VarCorr Notice that "ranef" in the prior release was out of step with everyone else, which became obvious when working on lmekin. Also, the constructs "fit$coef$random" and "fit$coef$fixed" no longer work due to some internal rea...