Displaying 20 results from an estimated 10000 matches similar to: "aov() question"
2007 May 15
3
aov problem
I am using R to make two-way ANOVA on a number of variables using
g <- aov(var ~ fact1*fact2)
where var is a matrix containing the variables.
However the outcome seem to be dependent on the order of fact1 and fact2
(i.e. fact2*fact1) gives a slightly (factor of 1.5) different result.
Any ideas why this is?
Thanks for any help
Anders
2004 Aug 11
2
type III sum of squares
R-help
What are the strengths and weakness of 'aov' in 'car' package?
My model looks something like this :
library(car)
aov(lm(fish.length~zone*area,data=my.data))
Thank you
Luis Ridao Cruz
Fiskiranns??knarstovan
N??at??n 1
P.O. Box 3051
FR-110 T??rshavn
Faroe Islands
Phone: +298 353900
Phone(direct): +298 353912
Mobile: +298 580800
Fax:
2007 Jul 09
2
ANOVA: Does a Between-Subjects Factor belong in the Error Term?
I am executing a Repeated Measures Analysis of Variance with 1 DV (LOCOMOTOR
RESPONSE), 2 Within-Subjects Factors (AGE, ACOUSTIC CONDITION), and 1
Between-Subjects Factor (SEX).
Does anyone know whether the between-subjects factor (SEX) belongs in the
Error Term of the aov or not? And if it does belong, where in the Error Term
does it go? The 3 possible scenarios are listed below:
e.g.,
1.
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 <-
2004 Apr 18
1
multistratum glm?
Hello,
I routinely use aov and and the Error term to perform analyses of
variance of experiments with 'within-subject' factors. I wonder whether
a notion like 'multistratum models' exists for glm models when
performing a logit analysis (without being 100% sure whether this would
make sense).
I have data of an experiment where the outcome is a categorical variable:
20
2004 Aug 10
4
Enduring LME confusion… or Psychologists and Mixed-Effects
Dear ExpeRts,
Suppose I have a typical psychological experiment that is a
within-subjects design with multiple crossed variables and a continuous
response variable. Subjects are considered a random effect. So I could model
> aov1 <- aov(resp~fact1*fact2+Error(subj/(fact1*fact2))
However, this only holds for orthogonal designs with equal numbers of
observation and no missing values.
2008 Jul 09
2
Read.table - Less rows than original data
Dear all,
I have problem when reading a table into R. The total row of read in table
has is much less than the original saved table.
I built a 1,273,230 by 6 data set named "mydata2", it was saved in the
following command,
write.table(mydata2, "mydata2.txt", row.name=F,col.name=T,quote=F,sep="\t")
The next day I read in above saved text file into R,
2007 Mar 08
1
R: Searching and deleting elements of list
you could try mapply
mydata2<-mapply("[", mydata, lapply(mydata, function(x) !x %in% A))
mydata2[[1]]<-A #to replace the obviously deleted elements of "A"
mydata2
mydata2[[1]]
mydata2[[2]]
mydata2[[3]]
mydata2[[4]]
Stefano
-----Messaggio originale-----
Da: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch]Per conto di jastar
2001 Dec 19
2
How to create a data.frame "like" another, but longer?
Hello,
does anyone know of a quick way to create a data frame "like" another, but
with more rows?
What I'd like to do is this:
if mydata is a data.frame like
a b c
1 TRUE yes
2 FALSE no
3 TRUE yes
I'd like to get mydata2 with the same column names and column types, but
without the values and with more rows.
All I could think of was to manually do
2006 Feb 20
3
Boxplot Help for Neophyte
R helpers
I am getting to grips with R but came across a small problem today that I
could not fix by myself.
I have 3 text files, each with a single column of data. I read them in
using:
myData1<-scan("C:/Program Files/R/myData1.txt")
myData2<-scan("C:/Program Files/R/myData2.txt")
myData3<-scan("C:/Program Files/R/myData3.txt")
I wanted to produce a
2003 Dec 09
2
PROC MIXED vs. lme()
I'm trying to learn how to do a repeated measures ANOVA in R using lme().
A data set that comes from the book Design and Analysis has the following
structure: Measurements (DV) were taken on 8 subjects (SUB) with two
experimental levels (GROUP) at four times (TRIAL).
In SAS, I use the code:
PROC MIXED DATA=[data set below];
CLASS sub group trial;
MODEL dv = group trial group*trial;
2008 Jul 09
1
read.table problem
Dear all,
I have problem when reading a table into R. The total row of read in table
has is much less than the original saved table.
I built a 1,273,230 by 6 data set named "mydata2", it was saved in the
following command,
write.table(mydata2, "mydata2.txt", row.name=F,col.name=T,quote=F,sep="\t")
The next day I read in above saved text file into R,
2004 Jan 20
2
repeated measurements with R
Hello All,
I have a more statistical question, and how this is implemented in R.
The problem is the following:
We have 2 different solutions (samples), which are filtered and then
the concentration of the filtrate is measured.
We want to evaluate how the filter proces and the concentration
measurement influences the detection of the difference of the two
solutions and which step has which
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
2012 Jul 03
1
insert missing dates
Hello
I have dataframes.
mydata1 <-data.frame(value=c(15,20,25,30,45,50),dates=c("2005-05-25 07:00:00
","2005-05-25 19:00:00","2005-06-25 07:00:00","2005-06-25 19:00:00
","2005-07-25 07:00:00","2005-8-25 19:00:00"))
or
mydata2 <-data.frame(value=c(15,20,25,30,45,50),dates=c("2005-05-25 00:00:00
","2005-05-25
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: