Displaying 20 results from an estimated 5000 matches similar to: "FW: Re: Doubt about nested aov output"
2005 Sep 07
1
FW: Re: Doubt about nested aov output
Ronaldo,
Further to my previous posting on your Glycogen nested aov model.
Having read Douglas Bates' response and Reflected on his lmer analysis
output of your aov nested model example as given.The Glycogen treatment has
to be a Fixed Effect.If a 'treatment' isn't a Fixed Effect what is ? If
Douglas Bates' lmer model is modified to treat Glycogen Treatment as a
purely
2006 Aug 30
1
lmer applied to a wellknown (?) example
Dear all,
During my pre-R era I tried (yes, tried) to understand mixed models by
working through the 'rat example' in Sokal and Rohlfs Biometry (2000)
3ed p 288-292. The same example was later used by Crawley (2002) in his
Statistical Computing p 363-373 and I have seen the same data being used
elsewhere in the litterature.
Because this example is so thoroughly described, I thought
2003 Mar 21
2
Trying to make a nested lme analysis
Hi,
I''m trying to understand the lme output and procedure.
I''m using the Crawley''s book.
I''m try to analyse the rats example take from Sokal and Rohlf (1995).
I make a nested analysis using aov following the book.
> summary(rats)
Glycogen Treatment Rat Liver
Min. :125.0 Min. :1 Min. :1.0 Min. :1
1st Qu.:135.8
2003 Feb 13
1
fixed and random effects in lme
Hi All,
I would like to ask a question on fixed and random effecti in lme. I am
fiddlying around Mick Crawley dataset "rats" :
http://www.bio.ic.ac.uk/research/mjcraw/statcomp/data/
The advantage is that most work is already done in Crawley's book (page 361
onwards) so I can check what I am doing.
I am tryg to reproduce the nested analysis on page 368:
2008 Apr 04
1
lme4: How to specify nested factors, meaning of : and %in%
Hello list,
I'm trying to figure out how exactly the specification of nested random
effects works in the lmer function of lme4. To give a concrete example,
consider the rat-liver dataset from the R book (rats.txt from:
http://www.bio.ic.ac.uk/research/mjcraw/therbook/data/ ).
Crawley suggests to analyze this data in the following way:
library(lme4)
attach(rats)
Treatment <-
2011 Mar 14
0
Non-constancy of variances in mixed model.
Hi, I've been doing an experiment, measuring the dead-zone-diameters of
bacteria, when they've been grown with paper diffusion disks of
antimicrobial. There are two groups, or treatments - one is bacteria
that have been cultured in said antimicrobial for the past year, the
other group is of the same species, but lab stock and has not gone had
any prior contact with the antimicrobial.
2005 Aug 30
2
Doubt about nested aov output
Hi,
I have two doubts about the nested aov output.
1) I have this:
> anova.ratos <- aov(Glicogenio~Tratamento+Error(Tratamento/Rato/Figado))
> summary(anova.ratos)
Error: Tratamento
Df Sum Sq Mean Sq
Tratamento 2 1557.56 778.78
Error: Tratamento:Rato
Df Sum Sq Mean Sq F value Pr(>F)
Residuals 3 797.67 265.89
Error: Tratamento:Rato:Figado
2005 Oct 20
0
lmer and grouping fators
Hi,
I make this model using lme
m.lme <- lme(Glycogen~Treatment,random=~1|rTrt/Liver)
How to make this using lmer?
I try
> m.lmer <- lmer(Glycogen~Treatment+(1|rTrt/Liver))
Erro em lmer(Glycogen ~ Treatment + (1 | rTrt/Liver)) :
entry 0 in matrix[0,0] has row 2147483647 and column 2147483647
Al??m disso: Mensagem de aviso:
/ not meaningful for factors in: Ops.factor(rTrt, Liver)
2005 Jun 02
0
How to calculate the correct SE in a nested or spliplot anova?
Hi!
How to calculate the correct SE of mean in a nested or spliplot anova?
Nested example:
---------------------
m <- aov(Glycogen~Treatment+Error(Treatment/Rat/Liver))
> m
Call:
aov(formula = Glycogen ~ Treatment + Error(Treatment/Rat/Liver))
Grand Mean: 142.2222
Stratum 1: Treatment
Terms:
Treatment
Sum of Squares 1557.556
Deg. of Freedom 2
Estimated
2007 Dec 20
1
hierarchical linear models, mixed models and lme
Dear R-users,
I am trying to analyse the data of the box 10.5 in the Biometry from
Sokal and Rohlf (2001) using R. This is a three-level nested anova with
equal sample size : 3 different treatments are compared ; 2 rats (coded
1 or 2) / treatment are studied ; 3 preparations (coded 1, 2 or 3) /
rats are available ; 2 readings of the glycogen content / preparations
are realised. Treatment is
2005 Mar 30
6
French Curve
Dear R experts,
Did someone implemented French Curve yet? Or can anyone point me some
papers that I can follow to implement it?
thanks in advance for your help.
Paul
2011 Sep 20
1
A question regarding random effects in 'aov' function
Hi,
I am doing an analysis to see if these is tissue specific effects on the
gene expression data .
Our data were collected from 6 different labs (batch effects). lab 1 has
tissue type 1 and tissue type 2, lab 2 has tissue 3, 4,5,6. The other labs
has one tissue type each. The 'sample' data is as below:
2003 Nov 05
2
Multiple comparisons with a glm
I've never seen anything written about multiple comparisons,
as in the multcomp package or with TukeyHSD, but using a glm.
Do such procedures exist? Are they sensible?
Are there any packages in R that implement such comparisons?
Thank you.
--
Ken Knoblauch
Inserm U371
Cerveau et Vision
18 avenue du Doyen Lepine
69675 Bron cedex
France
Tel: +33 (0)4 72 91 34 77
Fax: +33 (0)4 72 91 34 61
2006 May 18
1
adding grid lines to an xyplot when there is only 1 panel - corrected
Sorry, some things got garbled in that request for help that might make
my request
unintelligible, probably it being too late at night when I posted, here
is the corrected function
call for which I would like to learn how to add horizontal grid lines.
Any suggestions
would be appreciated. Apologies for the posting error
xyplot(est ~ STE, data = all, groups = AREA, type = "b",
2006 Nov 18
1
deriv when one term is indexed
Hi,
I'm fitting a standard nonlinear model to the luminances measured
from the red, green and blue guns of a TV display, using nls.
The call is:
dd.nls <- nls(Lum ~ Blev + beta[Gun] * GL^gamm,
data = dd, start = st)
where st was initally estimated using optim()
st
$Blev
[1] -0.06551802
$beta
[1] 1.509686e-05 4.555250e-05 7.322720e-06
$gamm
[1] 2.511870
This works fine but I
2006 Oct 07
1
Installing Lindsey's packages
Dear r-helpers,
I downloaded http://popgen.unimaas.nl/~jlindsey/rcode/rmutil.tar (it
was originally .tgz, but got unzipped by my browser).
Can anyone give me detailed instructions on installing this and
Lindsey's other packages on R version 2.4.0 (2006-10-03)---(powerpc-
apple-darwin8.7.0, locale: C)?
_____________________________
Professor Michael Kubovy
University of Virginia
2007 May 03
4
Survival statistics--displaying multiple plots
Hello all!
I am once again analyzing patient survival data with chronic liver disease.
The severity of the liver disease is given by a number which is continuously
variable. I have referred to this number as "meld"--model for end stage
liver disease--which is the result of a mathematical calculation on
underlying laboratory values. So, for example, I can generate a Kaplan-Meier
plot
2010 Sep 24
1
Fitting GLMM models with glmer
Hi everybody:
I?m trying to rewrite some routines originally written for SAS?s PROC
NLMIXED into LME4's glmer.
These examples came from a paper by Nelson et al. (Use of the
Probability Integral Transformation to Fit Nonlinear Mixed-Models
with Nonnormal Random Effects - 2006). Firstly the authors fit a
Poisson model with canonical link and a single normal random effect
bi ~ N(0;Sigma^2).The
2006 Sep 03
2
Running cox models
Hi,
I'm reading van Belle et al "Biostatistics" and trying to run a cox test using
a dataset from:
http://faculty.washington.edu/~heagerty/Books/Biostatistics/chapter16.html
(Primary Biliary Cirrhosis data link at top of the page),
I'm using the following code:
--------------- start of code
library(survival)
liver <-
2005 Oct 05
8
R crashes for large formulas in lm() (PR#8180)
Full_Name: Hallgeir Grinde
Version: 2.1.1
OS: Windows XP
Submission from: (NULL) (144.127.1.1)
While using lm(y~(x*z*c*...*v)^2) R crashes/closes if the numbers of variables
are at least 8.