Displaying 20 results from an estimated 8000 matches similar to: "nested anova and multiple comparisons"
2012 Feb 06
1
multiple comparisons in nested design
Dear professors and collegues
I need to perform a analysis of dates from a nested experimental design.
From
"Bioestatical Analysis" of Zar
"Bimetry of Sokal" & Rohlf
"Design and Analysis of Experiments" of Montgomery
I have:
Sum (mean(x)_i - mean(x)_T)2 / (a-1) -> var(epsilon) + n sigma2_B + n b
(sum alfa_i)2 / (a-1)
Sum (mean(x)_ij - mean(x)_i)2 /
2010 Jun 06
1
Why did TukeyHSD not work when I used it for post-hoc for 2way within-subjects anova?
Dear R people,
I have a couple of questions about post-doc analyses for 2 by 2 within
subjects ANOVA. I conducted a psycholinguistic study that combined a 2 by 2
design and a latin square design. Specifically, I had 32 items each of which
generated 4 conditions. Participants saw each of the 32 items only once: 8
in Condition A, 8 in B, 8 in C, and 8 in D. The table below serves as an
example.
2008 May 28
2
Tukey HSD (or other post hoc tests) following repeated measures ANOVA
Hi everyone,
I am fairly new to R, and I am aware that others have had this
problem before, but I have failed to solve the problem from previous
replies I found in the archives.
As this is such a standard procedure in psychological science, there
must be an elegant solution to this...I think.
I would much appreciate a solution that even I could understand... ;-)
Now, I want to calculate a
2007 Jun 28
2
TukeyHSD
Hello everyone,
So I ran an anova with aov and then I want to run post-hoc comparisons but
keep receiving this message :
> no applicable method for "TukeyHSD"
Here is my code:
> d<-read.table("d.txt")
> d
> Obs subj Hand Gaze RT
> 1 1 s1 1 1 401.4
> 2 2 s2 1 1 363.3......
> summary(ano <-
2006 Mar 28
2
TukeyHSD for repeated measures aov ?
Hi all,
I search the archive for finding a simple
solution for using TukeyHSD with a multistratum
aov result (a repeated emasure anova). The Question have
been asked but I've found no clear answer.
res<-aov(y~Fa*Fb+Error(Subject/(Fa*Fb)) )
I think that the problem is that res is an
aovlist object instead of the "aov" object required by TukeyHSD.
Is there an easy solution to
2012 Feb 04
5
Comparaciones múltiples en ANOVA anidadp
Dispongo de un experimento en el que cinco tratamientos ha sido
aplicados a cinco grupos de voluntarios.
En cada grupo había tres personas y a cada persona se le tomaron 3 medidas,
En total dispongo de 45 medidas, pero evidentemente no son
independientes entre sí. Si no tomo en cuenta que las medidas de la
misma persona son más parecidas entre sí (bloques anidados) estaría
incurriendo en
2012 Apr 03
1
Fisher's LSD multiple comparisons in a two-way ANOVA
Hi there,
Is there a function that can do a Fisher's LSD multiple comparisons in a
two-way ANOVA? I hope to get a result similar with TukeyHSD().
Especially, I hope to know the significance of comparisons between the
interactions of two factors.
In the following example:
x <- c(76, 84, 78, 80, 82, 70, 62, 72, 71, 69, 72, 74, 66, 74, 68, 66,
69, 72, 72, 78, 74, 71, 73, 67, 86, 67, 72,
2003 Aug 13
1
anova and tukeyHSD
I would like to do a one way anova and then a tukeyHSD. I have three vectors
A,B and C. In a previous help message, I was told to do the following for
the anova:
y = c(A,B,C)
group = factor(rep(a:3,c(7,9,13))) #provided there a 7 elements in A,9 in B
and 13 in C
and then
anova(lm(y~group))
Looking at the tukeyHSD method it looks like it wants the aov method which I
don't understand.
2008 Jul 30
2
Repeated Measure ANOVA-Old question
Hi R users,
I google the website and I found that there are three ways to perform
repeated measure ANOVA: aov, lme and lmer.
http://www.mail-archive.com/r-help at stat.math.ethz.ch/msg58502.html
But the questions are which one is good to use and how to do post-hoc test?
I use the example that is provided in the above link and I try
> tt<-aov(p.pa~group*time+Error(subject/time),data=P.PA)
2006 Jan 18
1
Within-Subjects ANOVA & comparisons of individual means
I am having problems with comparing individual means in a
within-subjects ANOVA. From my understanding, TukeyHSD is not
appropriate in this context. So I am trying to compute contrasts, as
follows:
seven subjects participated in each of 6 conditions (intervals).
> subject = factor(rep(c(1:7), each = 6))
> interval = factor(rep(c(1:6), 7))
and here is the dependent variable:
> dv
2002 Jul 01
1
How to do multiple comparisons with multiple error strata
Hello,
the title says it all. I have an ANOVA model with
"Error" term and the functions TukeyHSD or those
from the "multcomp" package seem not to work with
such a model. Assuming that the object returned from
aov() function with multiple strata is a list of aov objects,
I tried something like TukeyHSD(aov.1$Within), but this
does not work either.
Does somebody have a
2007 Mar 02
4
significant anova but no distinct groups ?
Dear all,
I am studying a dataset using the aov() function.
The independant variable 'cds' is a factor() with 8 levels and here is
the result in studying the dependant variable 'rta' with aov() :
> summary(aov(rta ~ cds))
Df Sum Sq Mean Sq F value Pr(>F)
cds 7 0.34713 0.04959 2.3807 0.02777
Residuals 92 1.91635 0.02083
The dependant variable
2009 Oct 19
1
Reposting various problems with two-way anova, lme, etc.
Hi,
I posted the message below last week, but no answers, so I'm giving it
another attempt in case somebody who would be able to help might have missed
it and it has now dropped off the end of the list of mails.
I am fairly new to R and still trying to figure out how it all works, and I
have run into a few issues. I apologize in advance if my questions are a bit
basic, I'm also no
2007 Nov 23
1
multiple comparisons/tukey kramer
Hi,
I'm trying to make sense of the options for multiple comparisons
options in R. I've found the following options:
pairwise.t.test, which provides standard t-tests, with options for
choosing an appropriate correction for multiple comparisons
TukeyHSD, which provides the usual Tukey test
glht(package multcomp), which provides a variety of options
>From the help list, it appears
2012 Jan 02
1
Is using glht with "Tukey" for lme post-hoc comparisons an appropriate substitute to TukeyHSD?
Hello,
I am trying to determine the most appropriate way to run post-hoc
comparisons on my lme model. I had originally planned to use Tukey
HSD method as I am interested in all possible comparisons between my
treatment levels. TukeyHSD, however, does not work with lme. The
only other code that I was able to find, and which also seems to be
widely used, is glht specified with Tukey:
2008 Sep 17
1
ANOVA contrast matrix vs. TukeyHSD?
Dear Help List,
Thanks in advance for reading...I hope my questions are not too ignorant.
I have an experiment looking at evolution of wing size [centroid] in
fruitflies and the effect of 6 different experimental treatments
[treatment]. I have five replicate populations [replic] in each
treatment and have reared the flies in two different temperatures [cond]
to assay the wing size, making
2010 Apr 29
1
R Anova Analysis
Dear all,
I have a quite basic questions about anova analysis in R, sorry for
this, but I have no clue how to explain this result.
I have two datasets which are named: nmda123, nmda456. Each dataset has
three samples which were measured three times. And I would like to
compare means of them with Posthoc test using R, following please see
the output:
(CREB, mCREB and No virus are the name of
2006 Jan 15
1
Multiple comparison and two-way ANOVA design
Dear useRs,
I'm working on multiple comparison design on two factor (2 3 levels)
ANOVA. Each of the tests I have tried (Tukey, multcomp package) seem to
do only with one factor at a time.
fm1 <- aov(breaks ~ wool * tension, data = warpbreaks)
tHSD <- TukeyHSD(fm1, "tension", ordered = FALSE)
$tension
diff lwr upr p adj
M-L -10.000000 -19.35342
2009 Oct 20
1
TukeyHSD no longer working with aov output?
I can prove I've done this before, but I recently installed Rexcel (and it
was easiest to reinstall R and some other bits to make it work) and now its
no longer working.
Before I would do an ANOVA and a tukey post-hoc like this:
>data1.aov=aov(result~factor1*factor2, data=data1)
then...
>TukeyHSD(summary(data1.aov))
and it would give me a nice tukey table of all the pairwise
2006 Feb 08
1
ERROR: no applicable method for "TukeyHSD"
Why do I see this error?
> library(stats)
> require(stats)
[1] TRUE
>
> tHSD <- TukeyHSD(aov)
Error in TukeyHSD(aov) : no applicable method for "TukeyHSD"
In case it helps:
> aov
Call:
aov(formula = roi ~ (Cue * Hemisphere) + Error(Subject/(Cue *
Hemisphere)), data = roiDataframe)
Grand Mean: 8.195069
Stratum 1: Subject
Terms:
Residuals
Sum