Displaying 20 results from an estimated 8000 matches similar to: "nlme questions"
2005 Jul 25
1
error in gnls
Dear R users;
I'm trying to fit nonlinear model (asymptotic regression model) with gnls
from library nlme in R 2.1.0 with no big issues so far. However after
installed the version R 2.1.1, when I tried to update the initial model
including a var-cov model I've got the error: "Error: Object "convIter" not
found". This error occurs only with R 2.1.1. Any ideas?
Thanks
2010 Aug 31
4
pasting together 2 character arrays
If possible I would like to combine two different character arrays in combinations
Array1 <- c("height","weight","age","sex")
Array2 <- c("trt0","trt1","trt2")
I would like to combine these two character vectors to end up with such ...
Array3
"height.trt0.trt1"
"height.trt0.trt2"
2004 Aug 02
4
Standard errors from glm
Kia ora list members:
I'm having a little difficulty getting the correct standard errors from a glm.object (R 1.9.0 under Windows XP 5.1). predict() will gives standard errors of the predicted values, but I am wanting the standard errors of the mean.
To clarify:
Assume I have a 4x3x2 factorial with 2 complete replications (i.e. 48 observations, I've appended a dummy set of data at the
2004 Jan 14
2
Generalized least squares using "gnls" function
Hi:
I have data from an assay in the form of two vectors, one is response
and the other is a predictor. When I attempt to fit a 5 parameter
logistic model with "nls", I get converged parameter estimates. I also
get the same answers with "gnls" without specifying the "weights"
argument.
However, when I attempt to use the "gnls" function and try to
2012 Sep 07
2
metafor package: study level variation
Hello. A quick question about incorporating variation due to study in the metafor package. I'm working with a particular data set for meta-analysis where some studies have multiple measurements. Others do not. So, let's say the effect I'm looking at is response to two different kinds of drug treatment - let's call their effect sizes T1 and T2. Some studies have multiple
2009 Apr 29
3
2 way ANOVA with possible pseudoreplication
Hi,
I have an experiment with 2 independant factors which I have been trying to
analyse in R. The problem is that there are several data points recorded on
the same animal. However, no combination of treatments is repeated on the
same animal. All possible combinations of treatments are done in a random
order with as many points as possible being done on 1 animal before moving
onto the next.
The
2001 Dec 03
3
beginner's questions about lme, fixed and random effects
I'm trying to understand better the differences between fixed and
random effects by running very simple examples in the nlme
package. My first attempt was to try doing a t-test in lme.
This is very similar to the Rail example that comes with nlme,
but it has two groups instead of five.
So I try
a1 <- 1:10
a2 <- 7:16
t.test(a2,a1)
getting t(18)=4.43, p=.0003224. Then I try to do it
2005 Dec 08
1
Operations on a list
Hello, Everyone,
I am sorry that my message got truncated.
I resend it again as below:
Hello, R Users,
I have a list (say listexp) of 10,000 elements, each of which consists of a
matrix (5X6). It likes:
$"a"
trt1rep1 trt1rep2 trt2rep1 trt2rep2 ctlrep1 ctlrep2
[1,] 50 54 98 89 40 45
[2,] 60 65 76 79
2012 Jan 13
1
plotting regression line in with lattice
#Dear All,
#I'm having a bit of a trouble here, please help me...
#I have this data
set.seed(4)
mydata <- data.frame(var = rnorm(100),
temp = rnorm(100),
subj = as.factor(rep(c(1:10),5)),
trt = rep(c("A","B"), 50))
#and this model that fits them
lm <- lm(var ~ temp * subj, data = mydata)
#i want to
2006 Sep 07
5
augPred plot in nlme library
All,
I'm trying to create an augPred plot in the nlme library, similar to the
plot on
p.43 of Pinheiro & Bates (Mixed Effects Models in S and S-Plus) for
their Pixel data.
My data structure is the same as the example but I still get the error
msg below.
> comp.adj.UKV <- groupedData(adj.UKV ~ Time | Patient_no/Lisinopril,
data = comp.adj.UKV.frm, order.groups = F)
>
2006 Sep 14
1
plotting all subgroups with augPred
All,
I have a question RE plotting the prediction lines of a random effects
model via augPred. I'll illustrate via the Pixel dataset within the
nlme package:
library(nlme)
attach(Pixel)
fm1Pixel = lme(pixel ~ day + I(day^2), data = Pixel, random = list(Dog =
~ 1))
plot(augPred(fm1Pixel)) ### 10 fitted lines since there are 10 dogs
fm2Pixel = update(fm1Pixel, . ~ . + Side)
2005 Apr 25
4
panel ordering in nlme and augPred plots
Dear all
I am trying nlme together with Pinheiro/Bates book. I constructed
grouped data object with suitable plotting layout (according to
some common factor, panels from bottom to top are in increasing
order).
When I do nlme(... some stuff...) I get fitted object which I can plot
with
plot(augPred(fit.nlme6, level=0:1))
but it results in completely different ordering. Is there any way
2004 Dec 01
2
unbalanced design
Hi all,
I'm new to R and have the following problem:
I have a 2 factor design (a has 2 levels, b has 3 levels). I have an
object kidney.aov which is an aov(y ~ a*b), and when I ask for
model.tables(kidney.avo, se=T) I get the following message along with
the table of effects:
Design is unbalanced - use se.contrast() for se's
but the design is NOT unbalanced... each fator level
2006 Aug 24
2
my error with augPred
Dear all
I try to refine my nlme models and with partial success. The model is
refined and fitted (using Pinheiro/Bates book as a tutorial) but when
I try to plot
plot(augPred(fit4))
I obtain
Error in predict.nlme(object, value[1:(nrow(value)/nL), , drop =
FALSE], :
Levels (0,3.5],(3.5,5],(5,7],(7,Inf] not allowed for
vykon.fac
>
Is it due to the fact that I have unbalanced
2017 Aug 23
2
strange nlme augpred behaviour
Hi
Well, yes I tried it about two weeks ago but my post did not get through as it still awaits moderator approval. I could check which column is offending but actually it is only minor nuisance, I can live with selection of columns before fitting a model. What seems to me strange is that both full dataset and only selected colums gave me identical fit results but only one works within augPred.
2017 Aug 23
2
strange nlme augpred behaviour
Dear all
I encountered strange behaviour of augPred with virtually the same data
First I made groupedData object.
> mar.g<-groupedData(rutilizace~doba|int, data=mar)
When I perform nlme on complete dataset I get an error with augPred
> fit<-nlsList(rutilizace~SSasymp(doba, Asym, R0, lrc), data=mar.g)
Warning message:
c("1 error caught in nls(y ~ cbind(1 - exp(-exp(lrc) * x),
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:
2006 Sep 04
1
abline and plot(augPred) help
Dear all
as I did not get any response on my post about abline and
plot(augPred)) I try again. I hope I do not break some posting guide
rules. I would try to contact package maintainer directly but there
is stated to be R-core people, so I feel R-help list shall be OK.
I need to draw straight lines through augPred plotted panels
(vertical or horizontal) at specified point. I know I shall
2017 Aug 24
0
strange nlme augpred behaviour
> On Aug 23, 2017, at 8:08 AM, PIKAL Petr <petr.pikal at precheza.cz> wrote:
>
> Hi
>
> Well, yes I tried it about two weeks ago but my post did not get through as it still awaits moderator approval.
It got through just fine. It appeared on Aug 15. It just didn't get any replies.
As I read your original question in this thread, it was not clear to me that you had
2007 Sep 15
1
Cannot get contrasts to work with aov.
I have been trying for hours now to perform an orthogonal contrast through an
ANOVA in R.
I have done a two-factor factorial experiment, each factor having three
levels. I converted this dataset to a dataframe with one factor with nine
treatments, as I couldn't work out what else to do.
I have set up a matrix with the eight orthogonal contrasts that I wish to
perform, but despite