Displaying 20 results from an estimated 2000 matches similar to: "Specifying spatial correlation Form in nmle"
2010 Apr 14
1
creating a new corClass for lme()
Hi,
I have been using the function lme() of the package nlme to model grouped
data that is auto-correlated in time and in space (the data was collected on
different days via a moving monitor). I am aware that I can use the
correlation classes corCAR1 and corExp (among other options) to model the
temporal and spatial components of the auto-correlation. However, as far as
I can tell, I can only
2005 Mar 22
2
LME correlation structures: user defined
Let me modify my question about user-defined covariance structures for LME models: Can somebody tell me how I can see the code for the definition of the correlation structures that come with the NLME package. Specifically I like to see the code for the functions coef, corMatrix, and intialize for any of the pre-defined correlation structures, and use this as a template to define a new correlation
2012 Jul 24
1
unable to run spatial lag and error models on large data
Hi:
First my apologies for cross-posting. A few days back I posted my queries ar R-sig-geo but did not get any response. Hence this post.
I am working on two parcel-level housing dataset to estimate the impact of various variables on home sale prices.
I created the spatial weight metrics in ArcGIS 10 using sale
year of four nearest houses to assign weights. Next, I ran LM tests and
then ran
2012 Aug 29
1
spatial correlation in lme and huge correlation matrix (memory limit)
Hi,
I'm trying to introduce a (spatial) exponential correlation
structure (with range=200 and nugget.effet of 0.3) in a lme model of
this form: lme(ARBUS~YEAR, random=~1|IDSOUS).
The structure of the data is "IDSOUS" "XMIN" "YMAX" "YEAR" "ARBUS"
with 2 years of data and 5600 points for each year.
I do:
2012 Aug 17
0
spatial auto-correlation structure in nlme
Dear R users,
I'm estimating a mixed effects model in which the spatial correlation is
controlled for by the "corGaus" structure. I'm wondering if there is a
document or paper that explains how the spatial correlation structure (such
as "corExp" or "corGaus") works.
Let me use the example and data posted on UCLA's R FAQ webpage to explain
my problems.
2009 Oct 21
1
odd evaluation within correlation argument of glmmPQL
[I think I've seen this reported before but can't locate it any more.
I believe this oddity (glitch? feature?) is behind a query that
Jean-Baptiste Ferdy asked a year ago
<http://finzi.psych.upenn.edu/Rhelp08/2008-October/176449.html>]
It appears that glmmPQL looks in the global workspace, not
within the data frame specified by the "data" argument, for
the variables
2006 Jul 01
1
nlme: correlation structure in gls and zero distance
Dear listers,
I am trying to model the distribution of fox density over years in the
Doubs department. Measurements have been taken on 470 plots in March
each year and georeferenced. Average density is supposed to be different
each year.
In a first approach, I would like to use a general model of this type,
taking spatial correlation into account:
2025 Jun 02
1
Specifying a long string literal across several lines
Like Tomas, I find the paste0 readability to be **much** better, partly
because it allows for better indentation (as Tomas pointed out). Perhaps a
pointless email, but sometimes - for these subjective issues - it is
worthwhile to point out a difference in opinion.
Best,
Kasper
On Mon, Jun 2, 2025 at 12:27?PM Tomas Kalibera <tomas.kalibera at gmail.com>
wrote:
>
> On 6/2/25 17:37,
2003 Jul 25
0
Memory explosion, plotting nmle grouped data object
Hi
I am using R 1.7.1 on RH linux 9.0
> sum(unlist(lapply(ls(),function(x)object.size(get(x)))))/1024^2
[1] 2.424263
so I am not using much memory (I have a gig of ram on my machine)
now in nlme
> gtest<-groupedData(log(X8)~Time|sub,all[,c(names(all)[1:9],"X8")],outer=~A*B)
> object.size(gtest)/1024
[1] 59.98438
> plot(gtest,outer=~Dose*chem,key=FALSE,asp=.5)
Plotting
2001 Dec 03
0
problems with nmle
Following the Indomethicin example in Pinheiro & Bates, chapter 6,
page 277 etc, coming to the following comand:
fm2Indom.nlme <- update( fm1Indom.nlme,
random = pdDiag(A1 + lrc1 + A2 ~ 1) )
debugging nlme gives the following output:
Browse[1]> n
debug: modelResid <- ~eval(model, data.frame(data, getParsNlme(plist,
fmap, rmapRel, bmap, groups, beta, bvec, b, level,
2005 Nov 16
0
nmle question
Hello.
I have 16 subjects with 1-4 obs per subject.
I am using the package "nlme" to fit a simple random effects (variance
components model) with 3 parameters: overall mean (fixed effect),
between subject variance (random) and within subject variance (random).
I need a 3x3 variance-covariance matrix that includes all 3 parameters
in order to compute the variance of a specific
2006 Nov 16
0
nmle for time of structural change?
Hi, All:
Does 'nlme' require the nonlinear function to be differentiable?
I'm fitting structural change models to many related time series, and
I'd like to improve the estimates of the change point times through some
type of pooling. Unfortunately, I've so far been unable to get 'nlme'
to work for me. The following toy example is the closest I've come
2005 Nov 09
0
source of "susbcript out of bounds error" in nmle
A few days ago I posted a question to this discussion group concerning
to origin of an error message < subscript out of bounds > while using
the nonlinear mixed model (nlme) function in R with a self-starting
function. Thanks for those who responded. This posting is to explain
what (I think) it causing the error.
Pinheiro & Bates (2000, pages 342-347) describe how to construct a
2007 Oct 17
2
nmle: gnls freezes on difficult case
Hi,
I am not sure this is a bug but I can repeat it, The functions and data
are below.
I know this is nasty data, and it is very questionable whether a 4pl
model
is appropriate, but it is data fed to an automated tool and I would
have hoped for an error. Does this repeat for anyone else?
My details:
> version
_
platform i686-pc-linux-gnu
2025 Jun 02
1
Specifying a long string literal across several lines
On 6/2/25 17:37, Josiah Parry wrote:
> Tomas,
>
> Here is a good example of where this functionality would be useful:
> https://github.com/R-ArcGIS/arcgislayers/blob/2b29f4c254e7e5a1dadce8d4b0015a70dfae39d4/R/arc-open.R#L19-L56
>
> In order to prevent R CMD check notes I have to use `paste0()` to
> concatenate long URLs. If we were able to use `\` to
> separate the string
2010 Jul 08
0
Psudeo R^2 (or other effect size) in spatial gls regressions
Dear all,
I have been using the function gls in the package nlme in R to fit some spatial
regressions (as described in Dormann et al.). However, I have been struggling
trying to find a way to calculate a measure of effect size from these models, so
I wanted to know if any of you had an idea on how to do this.
More precisely, I am producing a multiple model with an exponential correlation
2006 Nov 20
1
My own correlation structure with nlme
Dear all,
I am trying to define my own corStruct which is different from the
classical one available in nlme. The structure of this correlation is
given below.
I am wondering to know how to continue with this structure by using
specific functions (corMatrix, getCovariate, Initialize,...) in order to
get a structure like corAR1, corSymm which will be working for my data.
Thanks in advance.
2025 Jun 02
2
Specifying a long string literal across several lines
One could also argue that paste0("a", "b", "c") is a function call
that needs to be evaluated at runtime, whereas "abc" is a string
constant understood by the parser, and often also language agnostic.
I'd assume compilers and code- and text-search tools do a better job
with the latter.
/Henrik
On Mon, Jun 2, 2025 at 2:18?PM Josiah Parry
2025 Jun 02
2
Specifying a long string literal across several lines
I suppose taste is learned as well. It does feel quite odd that the best
way to define a long string without a note or text wrapping is by being
creative with functions.
This is valid in Python, Julia, and Rust (if you add `let` and a
terminating semi-colon):
my_str = "part1\
part2\
part2"
I don't think it is abnormal to expect or desire this type of functionality
in our favorite
2012 May 29
1
GLMMPQL spatial autocorrelation
Dear all,
I am experiencing problems using the glmmPQL function in the MASS package
(Venables & Ripley 2002) to model binomial data with spatial
autocorrelation.
My question - is the presence of birds affected by various hydrological
parameters?
Presence/absence data were collected from 83 sites and coupled against
hydrological data from the same site. The bird survey sampling effort