search for: rpsych

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 * dose + Error(subj/(dose*drug)), data=Ela.uni) b) Bill Venables answered a question on R help as follows. - factor A between subjects - factors B*C within sub...

...ue for the main effect of A. I can use summary(aov(value ~ b, data = ex)); to get the correct values for B(A) and the within cell SS. But I can't find any documentation about constructing the Error term to get this output in a single analysis (except for http://www.psych.upenn.edu/~baron/rpsych/rpsych.html, but Kirk doesn't talk about these tests in terms of Error strata, so it's a little hard to figure out the correspondence). Also, the documentation on the Error term in ?aov is rather perfunctory. There's no mention of the "/" operator, for example. ex = scan(...

For those new to this list, I point out that Yuelin Li and I have drafted an introduction to R for psychology, trying to emphasize the things the psychologists usually do. It is at http://www.psych.upenn.edu/~baron/rpsych.pdf and http://www.psych.upenn.edu/~baron/rpsych.htm Because it is a draft, with frequent changes, we have not yet asked for it to be placed in the CRAN page. We welcome suggestions for changes. One thing I want to add to it is a discussion of Error() in analysis of variance, once I understand it...

We now have a draft of: Notes on the use of R for psychology experiments and questionnaires by Jonathan Baron and Yuelin Li at http://www.psych.upenn.edu/~baron/rpsych.htm and http://www.psych.upenn.edu/~baron/rpsych.pdf and http://www.psych.upenn.edu/~baron/rpsych.tex It is intended for students and others who are doing research in psychology. What makes it "for psychology" is that it tries to cover the major statistical methods that psychologists u...

Dear all: I am totally new to R, actually, statistics software.I get two very simple, even stupid question: 1) where I should put the data file in order to use it , I tried to build a work dir in library( package:base) and save the text file (data) there, then, I use read.table(filename), not work; I tried the full path, still not work. I must have done something wrong. 2) is it possible to create

...r am I doing something wrong? 2. I have seen through Googling some dovecot.conf examples that suggest I should be using managesieve instead of lda (or in addition? - it's not clear), as in protocol managesieve { ... Any advice will be gratefully received. Thank you Cam -- Cam Ellison, PhD RPsych (BC #01417) Cam Ellison & Associates Ltd. 3446 Beach Avenue Roberts Creek BC V0N 2W2 Phone 604.885.4806 Fax 694.885.4809 Cell 604.989.0635

Dear Prof. Baron, thankyou for your pdf paper on using R, at http://www.psych.upenn.edu/~baron/rpsych.pdf I am currently interested in the sphericity notes on pp. 45-47. The equation on p. 46 suggests the following R calculation: D <- k^2 * ( mean(diag(S)) - mean(S) )^2 while the notes in the pdf indicate the following: D <- k^2 * ( mean(S) - mean(diag(S)) )^2 Can you please consider th...

...ns and present instead the output given by SPSS, or they are at a too advanced level for me. Any help would be really appreciated, Samuele References: - Baron,J. & Li,Y.(2004).Notes on the use of R for psychology experiments and questionnaires. Available: http://www.psych.upenn.edu/~baron/rpsych/rpsych.html

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

Hello, I have climatic data of various years with many missing values. I would like to know what tools in R are most suited to estimate this missing values. (New in R and quite new on statistics). Thanks, G

...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 an example using simple replicates. So, I made up the data below semi-borrowing the idea of a reaction time experiment involving noise from Maxwell, S. E. & Delaney, H. D. (1990) Designing Experiments and Analyzing Data: A model comparison perspecti...

Hi all, I've been reading about aov() at http://www.psych.upenn.edu/~baron/rpsych/rpsych.html and http://davidmlane.com/hyperstat/intro_ANOVA.html and I try to use this test in experiments with my simulator. What I would like Anova to tell me is whether the differences I see when plotting the means of performance per method are significant. And also, whether this is dependent o...

With respect to calculating the epsilon index of sphericity for ANOVA, discussed on pp. 45-47 of: http://www.psych.upenn.edu/~baron/rpsych.pdf It notes that epsilon is not required for a repeated measures design with only k=2 levels, as the minimum value of epsilon (e) is given by: e = 1/(k-1) so for k=2, we have e = 1 (ie, no correction of the F test df; see p. 46). These notes apply to a univariate F test. How do we estimate t...

Hi, we are just about to evaluate R as a standard statistics package for our institute. We looked around the help - manual, the FAQ, etc. and did not find anything for the topics of random factors in ANOVA, repeated measures in ANOVA, or within subjects designs in R. Could anyone point us to any information concerning - univariate approach to repeated measures anova - multivariate

..."Operating in S", from his text which can be found at: http://hesweb1.med.virginia.edu/biostat/s/doc/splus.pdf 2. Jon Baron says that he does not use the files R stores at all, instead following the procedures outlined in the beginning of his text: http://www.psych.upenn.edu/~baron/rpsych.htm This approach involves "...involves keeping raw data in separate files, each with a name (supposedly a useful mnemonic), such as cba1.data, and scripts in other separate files, such as cba1.R." A script is written to read, transform, manipulate, and analyze data. Jim Lemon uses a s...

...with random intercept and slope with lmer() or lme() B. Repeated measures ANOVA using aov() with Error() stratification (found in Baron & Li, 2006), something along the lines of: aov(outcome ~ group * time + baseline + Error(subj+subj:time)) (from: http://cran.r-project.org/doc/contrib/Baron-rpsych.pdf, p. 41) C. "Repeated measures" MANOVA as follows (using data in wide format): response <- cbind(time1,time2,time3,time4,time5,time6) mlmfit <- lm(response ~ group) mlmfit1 <- lm(response ~ 1) mlmfit0 <- lm(response ~ 0) # Test time*group effect anova.mlm(mlmfit, mlmfit1,...

I am writing course notes in LaTeX. In the part where I am describing model-fitting functions in R I want to use a ~ character inline. If I am displaying an example of R code in its own environment I use the alltt environment, which protects the ~ character. I have forgotten how to protect the ~ when I am writing something like The operator `~' is used to define a model formula in \R.

In Baron and Li's "Notes on the use of R for psychology experiments and questionnaires" http://cran.r-project.org/doc/contrib/rpsych.htm they describe a balanced data set for a drug experiment: "... a test of drug treatment effect by one between-subject factor: group (two groups of 8 subjects each) and two within-subject factors: drug (2 levels) and dose (3 levels). " This design is identical to an unbalanced one tha...

Hi all, I am trying to teach myself to use and program R (How else do you do it? lol) Anyway, I wrote a piece of code to compute coefficent alpha for a scale. As I am neither a statistician nor a programmer, I wanted people's feedback. The code appears to work (Win 95 with R 1.0.1) and I have verified my result with SPSS and it was correct (much to my astonishment!). Nonetheless, I am

Dear R members, Is there a way I can include more than one variable in a histogram? Many thanks in advance, Liqing, Liqing Zhang Department of Ecology & Evolutionary Biology 321 Steinhaus Hall U.C. Irvine Irvine, CA 92697-2525 Phone:(949)-824-7703 Fax: (949)-824-2181 Email: lzhang at uci.edu ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~