[R] numbering observations: help please!

Dear Friends, I have the very simple problem of needing to number observations in a data frame. After scratching the rest of my hair off my head without inspiration, I'm using a silly loop. I'm sure that there is a much more elegant and faster solution - can anyone help? Here is an example: my.

[R] peer-reviewed (or not) publications on R

Dear Friends, I'm contributing to a paper on a new R package for a clinical (medicine, ophthalmology) audience, and part of the mission is to encourage people who might be occasional users of Excel or SPSS, to become more familiar with R. I'd really appreciate any pointers to more recent papers th

[R] symmetric dotplot? (Wilkinson 1999, Am Stat 53 (3) 276-281

DeaR all, The stripchart function (graphics) is provides jittered and stacked univariate scatterplots, but I wonder if anyone has implemented a *symmetric* version of this - as in the lower panel of Wilkinson's paper: http://www.jstor.org/stable/2686111 I have looked through several functions i

Re: [R] off topic but need your pointers about statistics

his clear - mea culpa). A clearer heading might have attracted more readers. In my (personal) view none of the other lists you mention really compare to this one (R-help), but allstat might be added also. David Winsemius wrote: > > > On Jun 19, 2009, at 6:36 AM, Paul Artes wrote: &

Re: [R] off topic but need your pointers about statistics

Publication of "Exploratory Data Analysis" by John Tukey. Strange Tukey's name has not been mentioned so far. You should consider re-posting your most interesting question with a less apologetic title - perhaps you will get a larger range of replies. Best wishes Paul losemind wrote: > > Thank

[R] one-sample t-test with correlated (clustered) observations

I would like to estimate the difference between two measurement techniques. With both techniques, 4 measurements were obtained in each of 15 individuals. (These are not *repeated* measurements though - each of the 4 is of a different attribute). The naive approach would be a paired t-test, but of

Re: [R] psychometric functions

There is a nice paper by Yssaad-Fesselier and Knoblauch on "Modelling Psychometric Functions in R". http://hal.archives-ouvertes.fr/docs/00/13/17/99/PDF/B125.pdf You might also be interested in this: http://www.journalofvision.org/5/5/8/article.aspx which comes from the same group as the psignifi

[R] re cognizing patterns

DeaRs, i'm looking for some references on a statement as follows: "Humans are good at spotting trends and patterns in data, but they are also good at spotting those patterns where none really exist". This is not verbatim but there must be some scholarly work on this. I can't remember where I came

[R] independence of censoring in survival analyses

ne it empirically? (over and above some thinking about how censoring might be related to baseline factors). Would very much appreciate your thoughts and any pointers you can give Best wishes Paul aRtes = Paul H Artes, PhD Associate Professor & F