Displaying 20 results from an estimated 2000 matches similar to: "lme, mixed models, and nuisance parameters"
2004 Mar 18
1
two lme questions
1) I have the following data situation:
96 plots
12 varieties
2 time points
2 technical treatments
the experiment is arranged as follows:
a single plot has two varieties tested on it. if variety A on plot #1 has
treatment T1 applied to it, then variety B on plot #1 has treatment T2
applied to it. across the whole experiment variety A is exposed to
treatment T1 the same number of times as
2011 Oct 25
1
Unlist alternatives?
dfhfsdhf at ghghgr.com
I ran a simple lme model:
modelrandom=lmer(y~ (1|Test) + (1|strain), data=tempsub)
Extracted the BLUPs:
blups=ranef(modelrandom)[1]
Even wrote myself a nice .csv file....:
write.csv(ranef(modelrandom)[1],paste(x,"BLUPs.CSV"))
This all works great. I end up with a .csv file with the names of my strains
in the first column and the BLUP in the second
2006 Mar 21
1
Scaling behavior ov bVar from lmer models
Hi all,
To follow up on an older thread, it was suggested that the following
would produce confidence intervals for the estimated BLUPs from a linear
mixed effect model:
OrthoFem<-Orthodont[Orthodont$Sex=="Female",]
fm1OrthF. <- lmer(distance~age+(age|Subject), data=OrthoFem)
fm1.s <- coef(fm1OrthF.)$Subject
fm1.s.var <- fm1OrthF. at bVar$Subject
fm1.s0.s <-
2006 Sep 23
1
variance-covariance structure of random effects in lme
Dear R users,
I have a question about the patterned variance-covariance structure for the random effects in linear mixed effect model.
I am reading section 4.2.2 of "Mixed-Effects Models in S and S-Plus" by Jose Pinheiro and Douglas Bates.
There is an example of defining a compound symmetry variance-covariance structure for the random effects in a
split-plot experiment on varieties of
2008 Apr 28
2
F values from a Repeated Measures aov
Hi Folks,
I have repeated measures for data on association time (under 2
acoustic condtions) in male and female frogs as they grow to adulthood
(6 timepoints). Thus, two within-subject variables (Acoustic
Condition: 2 levels, Timepoint: 6 levels) and one between-subject
variable (Sex:male or female).
I am pretty sure my distributions depart from normality but I would
first like to simply run a
2010 Sep 16
1
ANOVA - more sophisticated contrasts
dear list,
i am using a multifactorial design with two treatments (factor A: drugs,
three levels; factor B: theraphy, two levels) and a time factor (three
levels, different timepoint). hypothetically, i measured the same subjects
for all treatements and timepoints, so its a repeated measurement design.
now i ran an anova in R and also some Tukey post-hoc tests using glht. but
what i am actually
2010 Sep 19
1
boyplots nearly identical but still highly significant effect?
dear list,
i am running a within-design ANOVA with 4 factors (4,4,2 and 2 levels each).
the last one is a time factor comprising two different treatment timepoints.
i fit a mixed-effects model using lme and apply the anova function to the
outcome. according to this analysis, there are highly significant main
effect on the first and the time factor. i then checked the boxplots for the
two 4-level
2009 Oct 25
3
Importing data from text file with mixed format
Hi,
I'm having difficulty importing my textfile that looks something like this:
#begin text file
Timepoint 1
ObjectNumber Volume SurfaceArea
1 5.3 9.7
2 4.9 8.3
3 5.0 9.1
4 3.5 7.8
Timepoint 2
ObjectNumber Volume SurfaceArea
1 5.1
2009 Sep 02
2
Average over data sets
Hello,
I have a number of files output1.dat, output2.dat, ... , output20.dat,
each of which monitors several variables over a fixed number of
timepoints. From this I want to create a data frame which contains the
mean value between all files, for each timepoint and each variable.
The code below works, but it seems like I should be able to do the
second part without a for loop. I played
2007 Nov 20
1
Vectorization/Speed Problem
Hi,
I cannot find a 'vectorized' solution to this 'for loop' kind of problem.
Do you see a vectorized, fast-running solution?
Objective:
Take the value of X at each timepoint and calculate the corresponding value
of Y. Leading 0's and all 1's for X are assigned to Y; otherwise Y is
incremented by the number of 0's adjacent to the last 1. The frequency and
2004 Mar 19
1
lme: simulate.lme in R
The goal: simulate chi square mixture distributions as a way of
simulating likelihood ratio test statistics for some mixed models where
the more specific model has some zero variance components (a la Pinheiro
and Bates pg. 84-87)
The problem: R doesn't have the function ms which is apparently used by
simulate.lme
In the current version of nlme for R, is there a way around this? Is it
2010 Jun 10
1
do faster ANOVAS
Dear all R users,
I want to realize 800 000 ANOVAS and to store Sum of Squares of the effects. Here is an extract of my table data
Product attribute subject rep t1 t2 t3 … t101
P1 A1 S1 R1 1 0 0 … 1
I want to realize 1 ANOVA per timepoint and per attribute, there are 101 timepoints and 8 attributes so I want to realize 808 ANOVAS. This will be an ANOVA with two factors :
Here is one example:
2013 Feb 05
1
lmer - BLUP prediction intervals
Dear all
I have a model that looks like this:
m1 <- lmer(Difference ~ 1+ (1|Examiner) + (1|Item), data=englisho.data)
I know it is not possible to estimate random effects but one can
obtain BLUPs of the conditional modes with
re1 <- ranef(m1, postVar=T)
And then dotplot(re1) for the examiner and item levels gives me a nice
prediction interval. But I would like to have the prediction
2008 Mar 08
1
analysing mixed effects/poisson/correlated data
I am attempting to model data with the following variables:
timepoint - n=48, monthly over 4 years
hospital - n=3
opsn1 - no of outcomes
total.patients
skillmixpc - skill mix percentage
nurse.hours.per.day
Aims
To determine if skillmix affects rate (i.e. no.of.outcomes/total.patients).
To determine if nurse.hours.per.day affects rate.
To determine if rates vary between
2011 Apr 16
3
lme4 problem: model defining and effect estimation ------ question from new bird to R community from SAS community
Hi R community,
I am new bird to R and moved recently from SAS. I am no means expert on
either but very curious learner. So your help crucial for me to learn R.
I have already got positive expression.
I was trying to fit a mixed model in animal experiment but stuck at simple
point. The following similar example is from SAS mixed model pp 212.
# data
genetic_evaluation <-
2014 Apr 22
0
Bug#745419: Bug#745419: xen-utils-4.1: Pygrub fails to boot from LVM LV when something installed in the volume boot record
On Mon, 2014-04-21 at 15:43 +0200, Sjors Gielen wrote:
> Package: xen-utils-4.1
> Version: 4.1.4-3+deb7u1
> Severity: important
>
> When an LVM LV that serves as the root disk for a Xen DomU contains a boot
> loader (or possibly other data) in its volume boot record, pygrub fails to boot
> it, printing "Error: boot loader didn't return any data" before exiting.
2004 Feb 07
1
display functions in groupedData and lme
I'm trying to set up a mixed model to solve using lme. It will have 3
fixed effects, two random effects and two interaction terms.
I've been reading Pinheiro's and Bates's book on the nmle library, but
find the part about display functions to be unclear. When creating a
groupedData object from a data.frame, you need to enter a function of the
form: response ~primary|grouping
2008 Feb 05
1
Extracting level-1 variance from lmer()
All,
How does one extract the level-1 variance from a model fit via lmer()?
In the code below the level-2 variance component may be obtained via
subscripting, but what about the level-1 variance, viz., the 3.215072 term?
(actually this term squared) Didn't see anything in the archives on this.
Cheers,
David
> fm <- lmer( dv ~ time.num*drug + (1 | Patient.new), data=dat.new )
2008 Sep 11
1
plot of all.effects object
All,
I'm trying to plot an all.effects() object, as shown in the help for
all.effects and also Crawley's R book (p.178, 2007). The data has a repeated
measures structure, but I'm using all.effects for the simple lm() fit here.
Below is a reproducible example that yields the error message.
fm.ex = lm(dv ~ time.num*drug*X, data = dat.new)
fm.effects = all.effects(fm.ex, xlevels =
2014 Apr 21
7
Bug#745419: xen-utils-4.1: Pygrub fails to boot from LVM LV when something installed in the volume boot record
Package: xen-utils-4.1
Version: 4.1.4-3+deb7u1
Severity: important
When an LVM LV that serves as the root disk for a Xen DomU contains a boot
loader (or possibly other data) in its volume boot record, pygrub fails to boot
it, printing "Error: boot loader didn't return any data" before exiting.
I think this is because of the function "is_disk_image" on line 45 of