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...ations that provide guidance either way? Thanks for any assistance! Andrew -- Andrew Robinson Program Manager, ACERA Department of Mathematics and Statistics Tel: +61-3-8344-6410 University of Melbourne, VIC 3010 Australia (prefer email) http://www.ms.unimelb.edu.au/~andrewpr Fax: +61-3-8344-4599 http://www.acera.unimelb.edu.au/ Forest Analytics with R (Springer, 2011) http://www.ms.unimelb.edu.au/FAwR/ Introduction to Scientific Programming and Simulation using R (CRC, 2009): http://www.ms.unimelb.edu.au/spuRs/

...applied] statistics is linear regression ... ? Does this ring a bell for anyone? Thanks, Andrew -- Andrew Robinson Department of Mathematics and Statistics Tel: +61-3-8344-9763 University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599 http://www.ms.unimelb.edu.au/~andrewpr http://blogs.mbs.edu/fishing-in-the-bay/

I am wondering how to obtain the model/equation at each level automatically in a regression model with a few factors without looking at summary of the lm model. For example, consider lm.factors <- lm(y ~ x1 + factor(x2)*factor(x3)+x4*factor(x5)) The coefficients of lm.factors in summary(lm.factors) might be complicated. I would like to have the equation at each level from lm.factor. Could you

Hi, Can someone please offer me some guidance? I imported some data. One of the columns called "JOBTITLE" when imported was imported as a factor column with 416 levels. I subset the data in such a way that only 4 levels have data in "JOBTITLE" and tried running randomForest but it complained about "JOBTITLE" having more than 32 categories. I know that is the limit

Hi, Does anyone know if: with R can you take a set of numbers and aggregate them like you can in SPSS? For example, could you calculate the percentage of people who smoke based on a dataset like the following: smoke = 1 non-smoke = 2 variable 1 1 1 2 2 1 1 1 2 2 2 2 2 2 When aggregated, SPSS can tell you what percentage of persons are smokers based on the frequency of 1's and 2's. Can

...w function in full, and demonstrates its application in some simple test cases. Best wishes, Andrew -- Andrew Robinson Department of Mathematics and Statistics Tel: +61-3-8344-9763 University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599 http://www.ms.unimelb.edu.au/~andrewpr http://blogs.mbs.edu/fishing-in-the-bay/ -------------- next part -------------- ## The new function my.tapply <- function (X, INDEX, FUN=NULL, ..., simplify=TRUE) { FUN <- if (!is.null(FUN)) match.fun(FUN) if (!is.list(INDEX)) INDEX <- list(INDEX) nI <- length(INDEX)...

Dear R developers, This is a rather peculiar question, but nevertheless I would still need an answer for. It is about an R package which I created (namely QCA), and from versions 1.0-0 to 1.1-4 I had a co-author. The co-author recently withdrawn from the package development, but still requires to be left in the authors list and be cited for the package in the CITATION file. Obviously, one could

...l of Biosciences Reader & Associate Professor in Applied Statistics Tel: (+61) 0403 138 955 School of Mathematics and Statistics Fax: +61-3-8344 4599 University of Melbourne, VIC 3010 Australia Email: a.robinson at ms.unimelb.edu.au Website: http://www.ms.unimelb.edu.au/~andrewpr MSME: http://www.crcpress.com/product/isbn/9781439858028 FAwR: http://www.ms.unimelb.edu.au/~andrewpr/FAwR/ SPuR: http://www.ms.unimelb.edu.au/spuRs/ [[alternative HTML version deleted]]

Using the weight argument with a variance function in lme (nlme), you can allow for heteroscedasticity of the within-group error. Is there a way to do this for the other variance components? For example, suppose you had subjects, days nested within subjects, and visits nested within days within subjects (a fully nested two-way design) and you had, say men and women subjects. Could you allow for

Hi all, Does anybody have the experience of using optim to estimate variables with integral forms? here the code: trun.mean<- function(x) # t is the threshold { mu=x[1]; sigma=x[2]; t=x[3]; f <- function(x) (1/(sigma*sqrt(2*pi)))*exp(-(x-mu)^2/(2*sigma^2)); pdf.fun <- function(x) x*f(x); integrate(f,thre,upper=Inf)$value/integrate(pdf.fun,thre,upper=Inf)$value ; } when I

Dear All, I tried to use the boot function, provided in the boot package, in such a simple task as to create a bootstrap distribution of the mean of a vector x. I wrote: b <- boot(x, mean, R=200) Well, it doesn't work. I suspect it has something to do with what is called "second argument" of the "statistic" in the help page of boot. What is the second argument of

Hi, I have to build a logistic regression model on a data set that I have. I have three input variables (x1, x2, x3) and one output variable (y). The syntax of lrm function looks like this lrm(formula, data, subset, na.action=na.delete, method="lrm.fit", model=FALSE, x=FALSE, y=FALSE, linear.predictors=TRUE, se.fit=FALSE, penalty=0, penalty.matrix, tol=1e-7,

Hi everyone, I am fitting a bivariate smoothing model by using gam. But I got an error message like this: "Error in eigen(hess1, symmetric = TRUE) : 0 x 0 matrix" If anyone know how to figure it out, pleaselet me know. Thanks very much. [[alternative HTML version deleted]]

Hi everybody, I am using predict.gam() now. I but it seems there is no such option to get standard errors of the predicted values. I tried to set se=T or se.fit=T but no use. If you know anything about that please let me know. Thanks very much. Kevin. [[alternative HTML version deleted]]

...-10 370 -1.520576e-10 4.003904e-10 371 -5.220764e-11 -4.587212e-10 372 3.234287e-10 1.484018e-09 -- Andrew Robinson Department of Mathematics and Statistics Tel: +61-3-8344-9763 University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599 http://www.ms.unimelb.edu.au/~andrewpr http://blogs.mbs.edu/fishing-in-the-bay/

[Originally sent this to r-help at lists.R-projects.org, but in case that's the wrong list I'm re-posting. Apologies if this becomes a re-post] -------------- next part -------------- An embedded message was scrubbed... From: Jonathon Kopecky <jkopecky at umich.edu> Subject: Need to fit a regression line using orthogonal residuals Date: Mon, 29 Jan 2007 14:52:24 -0500 Size: 1138

...different environments, using eval(), but I would prefer to avoid that if possible. Thanks, Andrew -- Andrew Robinson Department of Mathematics and Statistics Tel: +61-3-8344-9763 University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599 http://www.ms.unimelb.edu.au/~andrewpr http://blogs.mbs.edu/fishing-in-the-bay/

I'm investigating a number of dependent variables using mixed models, e.g. data.lmer45 = lmer(ampStopB ~ (type + stress + MorD)^3 + (1|speaker) + (1|word), data=data) The p-values for some of the 2-way and 3-way interactions are significant at a 0.05 level and I have been trying to find out how to understand the exact nature of the interactions. Does anyone know if it is possible to run

Hi, I try to make a model using lmer, but the weigths is not accept. m1<-lmer(ocup/total~tempo+(tempo|estacao),family=binomial,weights=total) Erro em lmer(ocup/total ~ tempo + (tempo | estacao), family = binomial, : object `weights' of incorrect type I dont understand why this error, with glm this work. the total object is a vector. Any idea? Thanks Ronaldo -- God is subtle, but

I`m doing some functions on C that gives me the x and y coordinates. I`d like to now how I can get these coordinates (both are a vector of number) on R to that I can make a graphic. I`ve already made a package with my functions, so I just wanna how about how to get the coordinates. Thanks, Heloise.