Displaying 20 results from an estimated 10000 matches similar to: "Random effects ANOVA?"
2012 Dec 02
1
Repeated-measures anova with a within-subject covariate (or varying slopes random-effects?)
Dear all,
I am having quite a hard time in trying to figure out how to correctly
spell out a model in R (a repeated-measures anova with a
within-subject covariate, I guess). Even though I have read in the
posting guide that statistical advice may or may not get an answer on
this list, I decided to try it anyway, hoping not to incur in
somebody's ire for misusing the tool.
For the sake of
2006 May 18
2
Running a likelihood ratio test for a logit model
Hi all --
I have to calculate a likelihood ratio test for a logit model. I
found logLik, but I need to calculate the log likelihood for the model
without any predictors. How can I specify this in glm? If the full
model is glm(y ~ x1), is the one without predictors (y ~ 0)? Or (y ~
1)?
Is there a more direct way of getting this?
-- Chris
2004 Aug 08
1
(REPOST) Simple main effects in 2-way repeated measure ANOVA
Hi all
I am running a 2-way repeated measure anova with 1 between-subjects
factor (Group=treatment, control), and 1 within-subject factor (Time of
measurement: time1, time2). I extract the results of the anova with:
summary(aov(effect ~ Group*Time + Error=Subj/Time, data=mydata))
Now, this must be clearly a dumb question, but how can I quickly
extract in R all the post-hoc t-tests for the
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.
2006 Apr 11
1
Specifying an appropriate error term in a hierarchical regression
Hi all --
So I'm working through my statistics homework again, and trying to
reproduce the examples in the book (Kirk's _Experimental Design_,
third edition) in R. This is a completely randomized hierarchical
design (CRH-28(A)). The B factor is completely nested within the A
factor. Pages 480-482, for those playing along at home.
I can use:
summary(aov(value ~ a + Error(b),
2006 Aug 03
3
between-within anova: aov and lme
I have 2 questions on ANOVA with 1 between subjects factor and 2 within factors.
1. I am confused on how to do the analysis with aov because I have seen two examples
on the web with different solutions.
a) Jon Baron (http://www.psych.upenn.edu/~baron/rpsych/rpsych.html) does
6.8.5 Example 5: Stevens pp. 468 - 474 (one between, two within)
between: gp
within: drug, dose
aov(effect ~ gp * drug *
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
2010 Mar 09
3
Help with ANOVA in R
Hi
I am attempting Anova analysis to compare results from four groups
(Samp1-4) which are lists of intensities from the experiment. I am
doing this by first creating a structured list of the data and then
conducting the ANOVA (Script provided below). Im an R beginner so am
not sure if I am using this correctly. Two major questions I have are:
1)
Is using the code (zzz.aov <- aov(Intensity ~
2008 Mar 07
1
Finding Interaction and main effects contrasts for two-way ANOVA
I've tried without success to calculate interaction and main effects
contrasts using R. I've found the functions C(), contrasts(),
se.contrasts() and fit.contrasts() in package gmodels. Given the url
for a small dataset and the two-way anova model below, I'd like to
reproduce the results from appended SAS code. Thanks. --Dale.
## the dataset (from Montgomery)
twoway <-
2010 Oct 17
1
unbalanced repeated measurements Anova with mixed effects
Dear R-list members,
I've been struggling with the proper setup for analysing my data. I've
performed a route choice experiment, in which participants had to make a
choice at each junction for the next road. During the experiment they
received traffic information, but also encountered two different
accidents. They also made trips without accidents.
What I'm interested in is to
2005 Apr 05
5
Help with three-way anova
Hi
I have data from 12 subjects. The measurement is log(expression) of a
particular gene and can be assumed to be normally distributed. The 12
subjects are divided into the following groups:
Infected, Vaccinated, Lesions - 3 measurements
Infected, Vaccintaed, No Lesions - 2 measurements
Infected, Not Vaccinated, Lesions - 4 measurements
Uninfected, Not Vaccinated, No Lesions - 3 measurements
2009 Jun 01
3
Within Subject ANOVA question
Dear R users,
I have copied for following table from an article on "Using confidence
intervals in within-subject designs":
Subject 1sec 2sec 5sec
1 10 13 13 12.00
2 6 8 8 7.33
3 11 14 14 13.00
4 22 23 25 23.33
5 16 18 20 18.00
6 15 17 17 16.33
7 1 1 4 2.00
8 12 15 17 14.67
9 9 12 12 11.00
10 8 9 12 9.67
I rearranged the data this way:
2003 Nov 16
1
SE of ANOVA (aov) with repeated measures and a bewtween-subject factor
Hallo!
I have data of the following design:
NSubj were measured at Baseline (visit 1) and at 3
following time points (visit 2, visit 3, visit 4).
There is or is not a treatment.
Most interesting is the question if there is a
difference in treatment between the results of visit 4
and baseline. (The other time points are also of
interest.) The level of significance is alpha=0.0179
(because of an
2007 Apr 13
2
replicates in repeated ANOVA
Hi,
I have sort of a newbie question. I've seriously put a lot of effort into how to handle simple replicates in a repeated ANOVA design, but haven't had much luck.
I really liked reading "Notes on the use of R for psychology experiments and questionnaires", by Jonathan Baron and Yuelin Li ( http://www.psych.upenn.edu/~baron/rpsych/rpsych.html ) but still didn't run across
2020 Oct 30
4
Sieve filter script EXECUTION FAILED
> On 30/10/2020 19:25 Bernd Petrovitsch <bernd at petrovitsch.priv.at> wrote:
>
>
> On 30/10/2020 17:11, @lbutlr wrote:
> [...]
> > echo $1 | sed -e '|</head>|<style>* {color:white !important; background-color: black !important; } </style></head>|'
>
> What should the sed stuff do?
> TTBOMK '|' is not known by sed ...
2006 Jul 20
2
(robust) mixed-effects model with covariate
Dear all,
I am unsure about how to specify a model in R and I thought of asking
some advice to the list. I have two groups ("Group"= A, B) of
subjects, with each subject undertaking a test before and after a
certain treatment ("Time"= pre, post). Additionally, I want to enter
the age of the subject as a covariate (the performance on the test is
affected by age),
2004 Oct 10
3
some help interpreting ANOVA results, please?
On Sun, 10 Oct 2004, RenE J.V. Bertin wrote:
> Could I ask some hints/help in interpreting the following ANOVA results,
> please? This concerns an experiment where I study the incidence and
> severity of motion sickness. I have Sickness.norm, a subjective
> discomfort/sickness estimate, normalised to 0..1, the session time T
> (normalised to 0..1 and binned in 0.2 wide bins) and a
2007 Nov 04
4
Why can repeated measures anova with within & between subjects design not be done if group sizes are unbalanced?
Dear R people:
I wish to switch from SPSS to R, but there is one particular type of
ANOVA design that cannot be done in R. Or more likely, it can be
done, but it is nowhere documented.
The problem is typical for psychologists:
You have a repeated measures design with different groups of subjects.
Now, this can be done with the aov command, but the number of
subjects in both groups must be
2005 Mar 18
1
slow computation of mixed ANOVA using aov
Dear R-help list,
I am trying to do a mixed ANOVA on a 8960 x 5 dataframe. I have 3 factors
for which I want to test all main effects and interactions : f1 (40 levels),
f2 (7 levels), and f3 (4 levels). I also have a subject factor, subject, and
a dependent variable, dv.
Some more information about the factors:
f2 is a between-subject factor. That is, for each level of f2 there are 8
nested
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.