Displaying 20 results from an estimated 600 matches similar to: "contrast in lme"
2007 May 03
2
Package contrast error
Trying to use contrast to look at differences within an lme
lme.fnl.REML <- lme(Max ~ S + Tr + Yr + Tr:Yr, random = ~1 |TID,
method = "REML")
I have three levels of Tr I'm trying to contrast among different
years (R, T97, T98), years = 1997-1999, so I'm interested in
contrasts of the interaction term.
> anova(lme.fnl.REML)
numDF denDF F-value
2011 Aug 17
1
contrast package with interactions in gls model
Hi!
I try to explain the efffect of (1) forest where i took samples's soils (*
Lugar*: categorical variable with three levels), (2) nitrogen addition
treatments (*Tra*: categorical variable with two levels) on total carbon
concentration's soil samples (*C: *continue* *variable) during four months
of sampling (*Time:* categorical and ordered variable with four levels).
I fitted the
2007 May 18
0
gls() error
Hi All
How can I fit a repeated measures analysis using gls? I want to start with a
unstructured correlation structure, as if the the measures at the occations are
not longitudinal (no AR) but plainly multivariate (corSymm).
My data (ignore the prox_pup and gender, occ means occasion):
> head(dta,12)
teacher occ prox_self prox_pup gender
1 1 0 0.76 0.41 1
2
2006 May 30
1
Query: lme output
Dear R-Users
I have a problem accessing some values in the output from the summary of an lme fit.
I fit the model below:
ggg <- lme (ST~ -1 + as.factor(endp):Z.sas + as.factor(endp), data=dat4a,
random=~-1 + as.factor(endp) + as.factor(endp):Z.sas|as.factor(trials),
correlation = corSymm(form=~1|as.factor(trials)/as.factor(id)), weights=varIdent(form=~1|endp))
hh
2005 Jun 28
1
How to extract the within group correlation structure matrix in "lme"
Dear R users,
I fitted a repeated measure model without random effects by using lme. I will use the estimates from that model as an initial estimates to do multiple imputation for missing values of the response variable in the model. I am trying to extract the within group correlation matrix or covariance matrix.
here is my code:
f = lme(y ~x0+x1+trt+tim+x1:tim +tim:trt,random=~-1|subj,
2006 Jun 01
2
Help: lme
Good day R-Users,
I have a problem accessing some values in the output from the summary of an lme fit.
The structure of my data is as shown below (I have attached a copy of the full data).
id trials endp Z.sas ST
1 1 -1 -1 42.42884
1 1 1 -1 48.12007
2 1 -1 -1 43.42878
2 1 1 -1
2006 Feb 12
1
lme, nlsList, nlsList.selfStart
Dear listers,
I am trying to fit a model using nlsList() using alternately a SSfol()
selfstart function or its developped equivalent formulae.
This preliminary trial works well
mydata<-groupedData(Conc~Tps|Organ,data=mydata)
mymod1<-nls(Conc~SSfol(Dose,Tps,lKe,lKa,lCl),data=mydata)
as well as a developped form:
mymod2<-nls(Conc~Dose * exp(lKe+lKa-lCl) *
2002 May 29
1
Extracting intercept and residual std dev from lme results
Greetings-
I need to extract, programatically, the standard deviations of the
intercept and residuals from an lme model. These are presented by
print.lme as:
...
(Intercept) Residual
StdDev: 1.410635 0.7800512
...
(data taken from ?lme's examples section)
I can get the residuals with x$sigma where x is the fitted lme object. I
can't find the intercept, though. The closest
2006 Feb 17
0
trouble with extraction/interpretation of variance struct ure para meters from a model built using gnls and varConstPower
Works perfectly. Thank you.
-Hugh Rand
-----Original Message-----
From: Spencer Graves [mailto:spencer.graves at pdf.com]
Sent: Sunday, January 15, 2006 6:41 PM
To: Rand, Hugh
Cc: 'r-help at lists.R-project.org'
Subject: Re: [R] trouble with extraction/interpretation of variance
structure para meters from a model built using gnls and varConstPower
How about this:
>
2009 Jan 28
0
How to stack data sets?
Hi All,
I'm generating 10 different data sets with 1 and 0 in a matrix form and writing the output in separate files. Now I need to stack all these data sets in one vector and I know that stack only operates on list or data frame however I got these data sets by converting list to a matrix so can't go backwards now. Is there a way i can still use Stack?
Please see the program:
2009 Jan 28
1
stack data sets
Hi All,
I'm generating 10 different data sets with 1 and 0 in a matrix form and writing the output in separate files. Now I need to stack all these data sets in one vector and I know that stack only operates on list or data frame however I got these data sets by converting list to a matrix so can't go backwards now. Is there a way i can still use Stack?
Please see the program:
2010 Nov 17
1
lme weights glht
Dear R-user
I used lme to fit a linear mixed model inlcuding weights=varPower().
Additionally I wanted to use glht to calculate Tukey-Kramer multiple
comparision.
error:
> glht(modelF, linfct=mcp(Species="Tukey"))
Error in glht.matrix(model = list(modelStruct = list(reStruct =
list(SubPlot = -0.305856275920955, :
?ncol(linfct)? is not equal to ?length(coef(model))?
>
2010 Sep 30
0
Problem comparing lme objects with anova using do.call
Hi all,
I am running some linear mixed models for longitudinal data using the nlme
package. Part of the code I've developed tests for differences among models
using the anova function, but I can't simply pass the corresponding lme
objects as parameters to the anova function because some of the models do
not converge and others are retained for comparison only if certain criteria
are met.
2005 Jan 24
0
Follow-up on nls convergence failure with SSfol
A couple of weeks ago there was a question regarding apparent
convergence in nls when using the SSfol selfStart model for fitting a
first-order pharmacokinetic model. I can't manage to find the original
message either in my archive or in the list archives but the data were
time conc dose
0.50 5.40 1
0.75 11.10 1
1.00 8.40 1
1.25 13.80 1
1.50 15.50 1
2006 Mar 07
1
lme and gls : accessing values from correlation structure and variance functions
Dear R-users
I am relatively new to R, i hope my many novice questions are welcome.
I have problems accessing some objects (specifically the random effects, correlation structure and variance function) from an object of class gls and lme.
I used the following models:
yah <- gls (outcome~ -1 + as.factor(Trial):as.factor(endpoint)+
2006 Jan 09
1
trouble with extraction/interpretation of variance structure para meters from a model built using gnls and varConstPower
I have been using gnls with the weights argument (and varConstPower) to
specify a variance structure for curve fits. In attempting to extract the
parameters for the variance model I am seeing results I don't understand.
When I simply display the model (or use "summary" on the model), I get what
seem like reasonable values for both "power" and "const". When I
2005 Jul 20
0
script.aculo.us 1.1 beta 1 ready
Get it here: http://script.aculo.us/downloads
Short take on what''s new:
-> Autocompletion took a notch up with incremental and local (js
array) functionality
-> Capability to remove draggables/droppables and redeclare sortables
-> Effect.ScrollTo
-> Fix memory leaks in IE and Gecko
-> Make some 3rd-party js libraries comaptible, namely IE7.js
-> Various tweaks and
2008 Dec 26
3
Simulating dataset using Parallel Latent CTT model?
I am trying to simulate a dataset using Parallel Latent CTT model and this is what i have done so far:
(START)
#Importing psych library for all the simulation related functions
library(psych)
# Settting the working directory path to C:/NCME
path="C:/NCME"
setwd(path)
#Using the function to generate the data
GenData <- congeneric.sim(N=500, loads =
2010 Feb 24
0
New version of rms package now on CRAN
Version 2.2-0 of the rms package is now available. This is a somewhat
major update. One major change is not downward compatible: Instead of
specifying predictor=. or predictor=NA to Predict, summary, nomogram,
survplot, gendata, you just specify the name of the predictor. For
example, to get predictions for the default range of x1 and for just 2
values of x2 you might specify Predict(fit,
2010 Feb 24
0
New version of rms package now on CRAN
Version 2.2-0 of the rms package is now available. This is a somewhat
major update. One major change is not downward compatible: Instead of
specifying predictor=. or predictor=NA to Predict, summary, nomogram,
survplot, gendata, you just specify the name of the predictor. For
example, to get predictions for the default range of x1 and for just 2
values of x2 you might specify Predict(fit,