Displaying 20 results from an estimated 8000 matches similar to: "lme and lmer df's and F-statistics again"
2008 Oct 10
4
how to store lme/lmer fit result
Dear R users,
I am building a hierarchical model on a large data set. It can take quite
some time to finish one fit, I was just wondering whether it is possible to
store the fit object (the result) to a file for later (offline) analysis.
thanks
Julia
--
View this message in context: http://www.nabble.com/how-to-store-lme-lmer-fit-result-tp19910951p19910951.html
Sent from the R help mailing
2004 Mar 16
3
Terminology and canonical statistical user literature
Brian Ripley wrote (to somebody asking about "effect sizes"):
> ...
> Given that, I wonder if you are used to standard terminology.
Good point. But I think for many of us there is more behind that.
I personally belong to an (apparently fairly large) group of
R users who may be enthusiastic, but are statistical laymen
due to a lack of formal education in the area.
The
2008 Feb 17
0
difference between lme and lmer in df calculation
Hello all. I'm currently working with mixed models, and have noticed
a curious difference between the nlme and lmer packages. While I
realize that model selection with mixed models is a tricky issue, the
two packages currently produce different AIC scores for the same
model, but they systematically differ by 2. In looking at the logLik
values for each method, I find that they
2006 Apr 22
1
Partially crossed and nested random factors in lme/lmer
Hi all,
I am not a very proficient R-user yet, so I hope I am not wasting people?s
time. I want to run a linear mixed model with 3 random factors (A, B, C)
where A and B are partially crossed and C is nested within B. I understand
that this is not easily possible using lme but it might be using lmer. I
encountered two problems when trying:
Firstly, I can enter two random factors in lmer but
2008 Jul 28
7
Legality Question about R's Open Source GNU GPL License
Hi,
I use R at home, and am interested in using it at my work company (which is
in the Fortune 100). I began the request, and our legal team has given some
gruff about the open source license. Not boring you with the details here,
but I used some info on gnu.org as a rebuttal, and someone at the company
replied that the generalities of GNU GPL may differ from R's specific GNU
GPL license,
2006 May 05
0
F-statistic in lme
Kevin
They do not exist. This question has come up often. Try the following to
see a thread
RSiteSearch('lmer p-values')
Harold
> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Hai Lin
> Sent: Friday, May 05, 2006 12:46 PM
> To: r-help at stat.math.ethz.ch
> Subject: [R] F-statistic
2009 Mar 04
0
F test in lmer quasipoisson
Hello !!
II'm trying to test for my fixed effects using an lmer with quasipoisson
errors.
Since my lmer model is corrected for overdispersion using this kind of
errors, I should use during model simplification in my Anovas *F test *and
not *Chi square test* to compare two models. So I write:
> anova(model,model2,test="F")
but R keeps performing a Chi square instead of the F
2006 Jan 05
1
Understanding and translating lme() into lmer() model
I am newbie in R, trying to understand and compare syntax in nlme and
lme4. lme() model from the nlme package I am interested in is:
lme.m1.1 = lme(Y~A+B+C,random=~1|D/E,data=data,method="ML")
(for simplicity reason, I am giving generic names of factors)
If I understand well, there are three fixed factors: A, B and C, and two
random factors: D and E. In addition to that, E is nested in
2010 Sep 10
2
lme vs. lmer, how do they differ?
windows Vista
R 2.10.1
What is the difference (or differences) between lme and lmer? Both appear to perform mixed effects regression analyses.
Thanks
John
John David Sorkin M.D., Ph.D.
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524
(Phone)
2010 Oct 26
1
lme vs. lmer results
Hello,
and sorry for asking a question without the data - hope it can still
be answered:
I've run two things on the same data:
# Using lme:
mix.lme <- lme(DV ~a+b+c+d+e+f+h+i, random = random = ~ e+f+h+i|
group, data = mydata)
# Using lmer
mix.lmer <- lmer(DV
~a+b+c+d+(1|group)+(e|group)+(f|group)+(h|group)+(i|group), data =
mydata)
lme provided an output (fixed effects and random
2011 Jan 21
1
TRADUCING lmer() syntax into lme()
---------- Forwarded message ----------
From: Freddy Gamma <freddy.gamma@gmail.com>
Date: 2011/1/21
Subject: TRADUCING lmer() syntax into lme()
To: r-sig-mixed-models@r-project.org
Dear Rsociety,
I'd like to kingly ask to anyone is willing to answer me how to implement a
NON NESTED random effects structure in lme()
In particular I've tried the following translation from lmer to
2006 Mar 28
0
Why is AIC from lmer 2 less than that from lme?
I'm migrating to lmer() from lme(). I have noticed that AIC values from
lmer() are 2 units smaller than those reported by lme(). Could someone
please explain why?
The issue can be replicated with the first example from Pinheiro & Bates
(2000) Mixed-effects models in S and S-plus.
library(nlme)
Rail2 <- Rail
summary(lme(travel~1,data=Rail2,random=~1|Rail)) # AIC = 128.177
2012 May 04
1
lme or lmer for unbalance data
Dear community,
I'd like to fix a mixed model. I have unbalance data, what should i use:
lme in nlme package , or lmer in lme4.
Thanks, user at host.com as user at host.com
--
View this message in context: http://r.789695.n4.nabble.com/lme-or-lmer-for-unbalance-data-tp4608425.html
Sent from the R help mailing list archive at Nabble.com.
2007 Oct 05
1
lme (or lmer) question
Folks:
In the following mixed effect model, the "x" and residual variance
components are nonidentifiable. Yet lme() (or the equivalent in lmer())
happily produces an answer in which the sum of the variance components is
the correct estimate of the single variance parameter. Why? -- i.e. why
doesn't lme complain?
x <- 1:50
y <- rnorm(50)
m1 <- lme( y ~ 1, rand = ~1|x)
2007 Jun 06
1
fixed effects anova in lme lmer
Can lme or lmer fit a plain regular fixed effects anova? Ie a model without a
random effect, or have there be at least one random effect in order for these
functions to work?
Trying to run such, (1) without specifying a random effect produces an error,
(2) specifying that there is no random effect does not produce the same output
as an anova run in lm(); (2b) specifying that there is no
2007 Oct 14
0
repeated measures - aov, lme, lmer - help
Dear all,
I'm not very sure on the use of repeated measures in R, so some advice
would be very appreciate.
Here is a simple example similar to my real problem (R 2.6.0 for
windows): Lets supose I have annual tree production measured in 9
trees during 3 years; the 9 trees are located in 3 different mountains
(sites), and each tree receive different annual rainfall (different
locations). I would
2006 Oct 06
1
Once again: aov vs. lme/lmer
First of all, I apologize for asking a question that has appeared
recurrently in this mailing list. However, I have googled for it, have
looked at the mailing list archives, and also looked at Pinheiro & Bates book
(although not very thoroughly, I must confess), to no avail.
Here is the question: I am trying to obtain with lme or lmer the same exact
numerical results (p-values) that I obtain
2009 Jul 12
0
Specifying a more complex covariance matrix in lme or lmer
Hi all,
I've searched threads and read up on some ways of doing this but I'm having
a hard time to get it to work. Here's my basic problem. I have the
following linear mixed model
y = Xb+Zu+e
where u~N(0,s^2*K) where K is a matrix.
I read a thread that basically suggested to decompose Zu into ZPD^(1/2)
D^(-1/2)P'u so that (D^(-1/2)P'u)~N(0,s'^2I) but I'm not sure
2017 Nov 27
0
How to extract coefficients from sequential (type 1) ANOVAs using lmer and lme
I wantto run sequential ANOVAs (i.e. type I sums of squares), and trying to getresults including ANOVA tables and associated coefficients for predictive variables(I am using the R 3.4.2 version). I think ANOVA tables look right, but believecoefficients are wrong. Specifically, it looks like that the coefficients arefrom ANOVA with ?marginal? (type III sums of squares). I have tried both lme
2012 Feb 07
1
lme, lmer, convergence
Hello, all,
I am running some simulations to estimate power for a complicated epidemiological study, and am using lme and lmer to get these estimates. I have to run a few thousand iterations, and once in a great while, an iteration will create fake data such that the model won't converge. I see from Google searches that this is not an uncommon situation.
My question: is there a way to