Displaying 20 results from an estimated 11000 matches similar to: "Question of nlme package"
2002 Feb 13
1
nlme package dependencies?
Dear R-help,
The following nlme example, from help(Variogram.gls), does not work on my
system.
> data(BodyWeight)
> fm1 <- gls(weight ~ Time * Diet, BodyWeight)
> Variogram(fm1, form = ~ Time | Rat)[1:10,]
Error in FUN(X[[1]], ...) : unused argument(s) (method ...)
It looks like I might not have loaded a necessary package. I did load nls
and lattice (the latter not actually being
2009 Apr 26
3
Question of "Quantile Regression for Longitudinal Data"
Hi,
I am trying to estimate a quantile regression using panel data. I am trying
to use the model that is described in Dr. Koenker's article. So I use the
code the that is posted in the following link:
http://www.econ.uiuc.edu/~roger/research/panel/rq.fit.panel.R
How to estimate the panel data quantile regression if the regression
contains no constant term? I tried to change the code of
2003 Jul 03
1
beginner gls (nlme) question
Hi all,
I am trying to get a handle on gls (package nlme). I have a toy problem: 3 fixed factors (A, B, C), two levels each, 5 replicates per treatment. The response variable is continuous, normal. I have a correlation matrix of the form:
> mat
A B C
A 1.00 0.75 0
B 0.75 1.00 0
C 0.00 0.00 1
which is common to all observations.
How do I construct the call to gls? I think I need to
2007 Nov 02
1
GLS with nlme
Hello All,
This is my third time attempting to post this message. I don't see it
in the archive, so I'm guessing it is not getting through. If I am
wrong, my apologies.
I am trying to do a GLS regression, (X'V^-1X)^-1X'V^-1y, using the gls()
function from the nlme package. I have the covariance matrix V. I have
been searching for a way to specify the correlation structure
2004 Oct 08
1
nlme vs gls
Dear List:
My question is more statistical than R oriented (although it originates
from my work with nlme). I know statistical questions are occasionally
posted, so I hope my question is relevant to the list as I cannot turn
up a solution anywhere else. I will frame it in the context of an R
related issue.
To illustrate the problem, consider student achievement test score data
with multiple
2005 Jul 15
1
nlme and spatially correlated errors
Dear R users,
I am using lme and nlme to account for spatially correlated errors as
random effects. My basic question is about being able to correct F, p, R2
and parameters of models that do not take into account the nature of such
errors using gls, glm or nlm and replace them for new F, p, R2 and
parameters using lme and nlme as random effects.
I am studying distribution patterns of 50 tree
2000 Jul 31
2
NLME 3 (R version) again!
Hi,
Well after trying to fix the assign commands in version 3.1.7 of your nlme package
I still cannot get the plot functions to work. Basically I have no other packages installed (apart from those provided with R) so nlme is the first.
my R version info is;
platform sparc-sun-solaris2.7
arch sparc
os solaris2.7
system sparc, solaris2.7
status
2012 Oct 01
6
nlme: spatial autocorrelation on a sphere
I have spatial data on a sphere (the Earth) for which I would like to run an gls model assuming that the errors are autcorrelated, i.e. including a corSpatial correlation in the model specification.
In this case the distance metric should be calculated on the sphere, therefore metric = "euclidean" in (for example) corSpher would be incorrect.
I would be grateful for help on how to
2006 May 17
1
nlme model specification
Hi folks,
I am tearing my hair out on this one.
I am using an example from Pinheiro and Bates.
### this works
data(Orange)
mod.lis <- nlsList(circumference ~ SSlogis(age, Asymp, xmid, scal),
data=Orange )
### This works
mod <- nlme(circumference ~ SSlogis(age, Asymp, xmid, scal),
data=Orange,
fixed = Asymp + xmid + scal ~ 1,
start =
2000 Mar 07
1
Problems with nlme (PR#471)
Dear R developers,
first of all let me join the chorus of congratulations for the release
of R 1.0.0. Well, done!
Unfortunately, I find it necessary to e-mail in a bug report regarding
the `nlme' package. On my office machine I experience the following
trouble:
bossiaea:/opt/R$ R CMD check -c nlme
Checking package `nlme' ...
Massaging examples into `nlme-Ex.R' ...
Running
2008 Mar 11
1
Problem comparing Akaike's AIC - nlme package
Hello,
I am comparing models made with nlme functions and non-nlme functions, based
on Akaike's AIC. The AIC values I get for exactly the same model formulation
--for example a linear model with no random effects fit with gls and lm,
respectively-- do not fit, although the values of the four model parameters
are exactly the same. For example:
m1 <- gls(height ~ age, data = Loblolly)
m2
2003 Oct 24
2
NLME: gls parameter evaluation inconsistency (PR#4757)
Full_Name: W.B.Kloke
Version: 1.8.0
OS: FreeBSD-4.7
Submission from: (NULL) (195.253.22.63)
I found a parameter evaluation inconsistency in NLME package. I tried to use
gls() inside a function, and I wanted use gls() for different subsets of a data
frame:
prgls <- function(name){ gls( log10(Y)~(cond-1)+(cond-1):t
,pr,subset=subject==name)}
Applying this function with a string as parameter
2005 Nov 17
1
anova.gls from nlme on multiple arguments within a function fails
Dear All --
I am trying to use within a little table producing code an anova
comparison of two gls fitted objects, contained in a list of such
object, obtained using nlme function gls.
The anova procedure fails to locate the second of the objects.
The following code, borrowed from the help page of anova.gls,
exemplifies:
--------------- start example code ---------------
library(nlme)
##
2006 May 15
1
what's wrong with my "gls"? it does not allocate memory... even for the simplest AR1 model...
> myfit1 <- gls(col1 ~ col2+col3+col4+col5+col6-1, data=data2, corr=corAR1(
0.3202), method='ML')
Error: cannot allocate vector of size 199712 Kb
if I get rid of the "corr=corAR1(0.3202)" option, it works okay...
can anybody help me?
thanks a lot!
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2008 May 09
1
Which gls models to use?
Hi,
I need to correct for ar(1) behavior of my residuals of my model. I noticed
that there are multiple gls models in R. I am wondering if anyone
has experience in choosing between gls models. For example, how
should one decide whether to use lm.gls in MASS, or gls in nlme for
correcting ar(1)? Does anyone have a preference? Any advice is appreciated!
Thanks,
--
Tom
[[alternative HTML
2004 Aug 26
1
gls: Newton-Raphson or EM?
Hello,
Does anyone know whether the gls function in the nlme library uses the Newton-Raphson or EM algorithm to find the restricted log-likelihood or maximum log-likelihood estimates?
Brendan Klick
bklick@jhsph.edu
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2004 Jul 01
2
Individual log likelihoods of nlsList objects.
Hello all.
I was wondering if the logLike.nls() and logLike.nlme() functions are still
being used. Neither function seems to be available in the most recent
release of R (1.9.1). The following is contained in the help file for
logLik(): "classes which already have methods for this function include:
'glm', 'lm', 'nls' and 'gls', 'lme' and others in
2024 Jul 16
2
Interpreting p values of gls in nlme
Dear all
I have undertaken some phylogenetic and non-phylogenetic regressions with
gls() in nlme with single preictor variables. A p value is associated with
the intercept (upper p value) and another with the predictor variable
(lower). Which p value is important? What does it mean if the intercept p
value is insignificant but the predictor is still significant?
Thanks a lot, and sorry for my
2024 May 03
1
Using intervals() function for nlme model - Statistics Lab ETHZ
Dear members of the R-Help Team,
we are reaching out to you with a question regarding using intervals()<https://www.rdocumentation.org/packages/nlme/versions/3.1-163/topics/intervals> to create inference for nlme()<https://www.rdocumentation.org/packages/nlme/versions/3.1-164/topics/nlme> function.
The maintainer for the nlme package is listed as the R-Core Team and we were advised
2017 May 10
2
bug report: nlme model-fitting crashes with R 3.4.0
lme() and gls() models from the nlme package are all crashing with R.3.4.0. Identical code ran correctly, without error in R 3.3.3 and earlier versions. The behavior is easily demonstrated using one of the examples form the lme() help file, along with two simple variants. I have commented the errors generated by these calls, as well as the lines of code generating them, in the code example below.