Displaying 20 results from an estimated 10000 matches similar to: "balance in AoV (was aov() and NaN)"
2002 Jul 05
1
aov() and NaN
hi,
another anova question !!
how does aov() treat missing values ?
since it might depend on my experimental design:
i have a within subject design with two factors ...
i use aov() like this:
aov(performance~type*block+Error(subj/(type+block)),data=anovaData)
now it might happen that i have a couple of NaN data points in my result
dataFrame.
how can i know/control how aov() is treating those
2002 Jul 04
1
rpart help please
Hi all,
I am trying to get to grips with rpart, and find it not very easy given the
information that comes with the package. Contrary to e.g. the ctest package docs, it
doesn't say when "an rpart" could be used, and/or how to interpret the results. Here
are a few of the open questions I have:
1) Read in ?rpart: ...method: one of.... If y is a survival object... A similar
1998 Aug 31
0
Packages aov, modreg, lqs, psplines
I now have versions of code that is destined (I believe) for 0.63 which
is in a suitable state for comment. The files are at
ftp://ftp.stats.ox.ac.uk/pub/R
(Our www server is being moved, so may be intermittently down, but this
ftp server should be stable.) All are R packages, for the moment for
personal use only (no re-distribution). Use with 0.62.3 or 0.63 (although
I am aware of some
2005 Feb 25
1
vcov on result of rlm() yields "-- please report!" (PR#7707)
Dear r-bugs,
I looked over the FAQ. Hope I'm reporting this correctly.
I ran this on both solaris and windows. I've provided terminal snapshots
which include how R was called from the command line, and the
result of version at the R prompt.
I have attached the .r file, and the data file and the output snapshots.
Below also find everything except only a few lines of the data file.
Note
2003 Mar 22
1
extracting the names of the dataframe and variables in aov or lm
Dear R Users,
I want to write a function that applies to the dataframe and variables
that were used in a previous call to lm or aov. In order to do this, I
need to write a function that applies to the output of lm or aov, and
yields the names of the dataframe and variables that were used in the lm
or aov analysis.
For example, suppose that I give the command:
aov.out <- aov( Rt ~
2008 Nov 26
1
S4 slot containing either aov or NULL
Dear listmembers,
I would like to define a class with a slot that takes either an object
of class aov or NULL. I have been reading "S4 Classes in 15 pages more
or less" and "Lecture: S4 classes and methods"
#First I tried with list and NULL
setClass(listOrNULL")
setIs("list", "listOrNULL")
setIs("NULL", "listOrNULL")
#doesn't
2008 Oct 29
2
how to get the value of aov summary into another variable
Hi,
I have a question of aov. e.g.
aov.ex = aov(x~y)
summary(aov.ex)
The aov summary will print to the screen. How can I extract the aov
result, in particular the values of Pr(>F) and F value into a vector
so that I can use them for other use?
Thanks.
--
Waverley @ Palo Alto
2010 Jan 09
2
aov function syntax
Hello,
I have a simple question about using the aov function syntax (ie. * + or :)
for the interaction of 2 factors. I have read the help files, and researched
other sites, and have included my source files. My goal is to measure the
signifigance of the interaction between population and condition (aka.
population:condition). I can't seem to figure it out.
1. In the first example the
2010 Apr 21
1
How to obtain the coefficients from a summary of aov ?
Dear Madame, Dear Sir,
I am able to obtain the coefficients from a 'summary' of 'lm', but NOT from a 'summary' of 'aov'.
The following example shows my steps.
## Initialize
rm(list = ls()) # remove (almost) everything in the working environment
utils::data(npk, package="MASS") # get data
model <- yield ~ block + N*P*K
## Using lm
npk.lm <-
2010 Nov 16
1
AOV/LME
Hi everyone,
I'm having a little trouble with working out what formula is better to use
for a repeated measures two way anova. I have two factors, L (five levels)
and T (two levels). L and T are both crossed factors (all participants do
all combinations). So, I do:
summary(aov(dat~L*T+Error(participant/(L*T)),data=dat4))
But get different results with:
2007 Jun 28
2
aov and lme differ with interaction in oats example of MASS?
Dear R-Community!
The example "oats" in MASS (2nd edition, 10.3, p.309) is calculated for aov and lme without interaction term and the results are the same.
But I have problems to reproduce the example aov with interaction in MASS (10.2, p.301) with lme. Here the script:
library(MASS)
library(nlme)
options(contrasts = c("contr.treatment", "contr.poly"))
# aov: Y ~
2005 Nov 08
1
Type II and III sums of squares with Error in AOV
I've recently run into the problem of using aov with nested factors,
and wanting to get the type II and III sums of squares. Normally Anova
from the car package would do fine, but it doesn't like having an Error
included, so
my.aov <-aov(Response ~ Treatment + Error(Treatment:Replicate))
Anova(my.aov, type="II")
yields
Error in Anova(nested.anova) : no applicable method
2008 Dec 17
1
repeated measures aov with weights
Dear R-help,
I'm facing a problem with defining a repeated measures anova with
weighted data.
Here's the code to reproduce the problem:
# generate some data
seed=11
rtrep <- data.frame(rt=rnorm(100),ti=rep(1:5,20),subj=gl
(20,5,100),we=runif(100))
# model with within factor for subjects/repeated measurements, no
problem
aov(rt~ti + Error(subj/ti),data=rtrep)
#model with weights
2013 Mar 06
1
aov() and anova() making faulty F-tests
Dear useRs,
I've just encountered a serious problem involving the F-test being carried
out in aov() and anova(). In the provided example, aov() is not making the
correct F-test for an hypothesis involving the expected mean square (EMS) of
a factor divided by the EMS of another factor (i.e., instead of the error
EMS).
Here is the example:
Expected Mean Square
2010 Mar 17
2
define F-ratio computations with aov
Greetings to all,
This is my model: aov.fit<-aov(Y~A+B+C+D+E+A:C+A:E)
In summary(aov.fit) all F values are comptuted by eg MS(A)/MS(Residuals). This is not correct (or what I want), except for F(B) and F(A:E). I suppose P values are not correct either.
Is it possible with aov to define the way F computations will be done? I 'd like them to be like this: F(A)=MS(A)/MS(E),
2012 Oct 08
2
aov() usage
Hi R-listers,
I am wondering if the function aov() in plyr is appropriate for two
different types of tests:
1) > summary(aov(EDI ~ VegIndex, data=data.to.analyze))
AND
2) > summary(aov(HSuccess ~ VegIndex + Aeventexhumed +
VegIndex:Aeventexhumed, data=data.to.analyze))
the later inclusive of an interaction of the two explanatory variables.
This is for obtaining P value and F
2007 Oct 07
1
Question about aov
Hello R gurus,
I am a beginner with R. I am doing an ANCOVA analysis using 'aov,' and need some help understanding how 'aov' works. I have a dataset (taken from http://faculty.vassar.edu/lowry/ch17pt2.html) looking at hypnotic induction. The variable 'X' is a measure of how susceptible the subject is to being hypnotized, the variable 'Y' is how well the
2020 Apr 11
1
Long model specification causes aov() to abort with error
Dear R developers,
while experimenting with repeated measures ANOVA, I found out that it is
possible to construct a model specification that is syntactically valid,
but causes aov() to abort with an error. A minimal reproducer and its
output are attached to this mail. I was able to reproduce this problem
with the latest SVN revision.
The root cause is similar to that of bug 15377: aov()
2005 Mar 10
1
contrast matrix for aov
How do we specify a contrast interaction matrix for an ANOVA model?
We have a two-factor, repeated measures design, with
Cue Direction (2) x Brain Hemisphere(2)
Each of these has 2 levels, 'left' and 'right', so it's a simple 2x2 design
matrix. We have 8 subjects in each cell (a balanced design) and we want to
specify the interaction contrast so that:
CueLeft>CueRght
2003 Apr 10
3
multiple numerical variables in aov
Hi all,
I have a question regarding the anova function aov(). I want to perform an anova calculation
using one grouping variable but more than one numerical variables:
So instead of:
aov(v ~ g)
I want something like
aov(v1 + v2 + v3 ~ g)
Essentially I want to find out whether the variables v1, v2, v3, etc can collectively discriminate
between different values of variable g. Could