search for: djw1005

When I alter the levels of a factor, why does it alter the names too? f <- factor(c(A="one",B="two",C="one",D="one",E="three"), levels=c("one","two","three")) names(f) -- gives [1] "A" "B" "C" "D" "E" levels(f) <-

I found this great search source("http://www.statslab.cam.ac.uk/~djw1005/Stats/Interests/search.R") helpHTML() Has (or will) this become the standard search method? Is R 'Free Software'? The dependence on Java seems a bit of a pain for 'freeness'. Did the above make it into CRAN? Cheers, Dan.

I am having trouble with ESS+R. I don't know if it is an ESS problem or an R problem, so I'm posting to this mailing list in the first instance. I am using R 1.6.2, Windows XP (latest updates installed), XEmacs 21.4, and ESS 5.1.21. I have experienced the same problem under Windows 2000 and recent versions of Emacs and ESS (though my current Windows XP installation is from scratch, and

...on Javascript rather than Java. (Hopefully, this means that there is less that can go wrong.) I haven't wrapped it up in a package yet, because I don't know how well it works or even if there is any interest. If you would like to try it, you can: source("http://www.statslab.cam.ac.uk/~djw1005/Stats/Interests/search.R") helpHTML() (Or you can download the code and run it locally. You will also need to download searchtemplate.html from the same location. You can then run helpHTML(searchTemplate=localfilename) to tell it to use your local copy of searchtemplate.html.) ISSUES WITH MY...

Why does > curve(function(y) y^2, from=0,to=1) not work, whereas > myf <- function(y) y^2 > curve(myf, from=0,to=1) work? For the former, I get the error message Error in curve(function(y) y^2, from = 0, to = 1) : 'expr' must be a function or an expression containing 'x' I'm using R1.7.0 under Windows XP. Damon Wischik.

I woud like to plot cumulative histograms. Specifically, I have data like Sex M M F M F F M F Height 6 6.3 6.1 5.5 7.2 6.2 5.9 6.0 .... and I want to plot a histogram of the distribution of all heights, colouring the histogram bars according to sex, for example | o | oo o | o oo ** o o = observations of women | o o*o***o * = observations of

I would be grateful for advice about the following problem. It's not directly R-related, but I'm hoping that R will help me analyse the following data. I have a table which indicates the progression of a certain age-related disease. At a certain point in time, a population was sampled; and I have measurements for the age of each individual, and their disease stage. (Disease stage is an

I had to reinstall my machine, so I installed Firefox 0.9 as browser I am using WinXP and R 1.9.1 beta. Now search in R html help does not work. I checked that the Java VM is working correctlt, Sun's test site says my installation is OK. Firefoxalso tells me that Applet Searchengine loaded Applet Searchengine started it just does not find anything. Does anybody know how to solve this? Erich

----- Original Message ----- From: "Richard A. O'Keefe" <ok at cs.otago.ac.nz> To: <paul at datavore.com> Sent: Thursday, September 04, 2003 2:56 AM Subject: Re: [R] Overlaying graphs > I do not know how to overlay the curve graphic on top of hist graphic. > > Do you know about the "add=TRUE" option for plot()? > > I am hoping to show visually

I'm using 1.6.2 on a win 2k box. (I know I'm due for an upgrade.) I've used brute force to label a series of vectors, and I'm wondering if there's a better way to do this. I wanted to create a biplot of the 2nd & 3rd PCs, and did this: test <- edit(loadings(cv.prc.spr)) test.1 <- test[,1] test.2 <- test[,2] test.3 <- test[,3] x0 <- 0 y0 <- 0 i <-

I want to plot biplots. I have seen the function biplot, but there are some extra features I would like, that I do not know how to achieve. 1. My observations, and my variables, fall into groups. Is there a way to, say, plot the observations in several different colours, according to which group the observation falls into? Similarly with the variables? I am used to the lattice idiom, in which one

I have data on a number of patients. Essentially, for each patient I know his/her age and whether he/she exhibits certain symptoms: age symptom1 symptom2 50 0 1 53 0 0 70 1 1 ... I have started off by fitting simple models with forms like Prob(patient of age t shows symptom i) = 1 - Exp(-lambda_i * t) or Prob(patient of age t shows

I'm having trouble with the HTML-based search engine, and I'd be grateful for any advice. I am using Mozilla Firebird 0.7 on Debian 3.0 with R 1.8.0. (I've also had the trouble with Mozilla Firebird 0.6 on Debian 3.0. I also use Mozilla Firebird 0.6 on Windows XP, and I have no trouble with the HTML-based search engine.) When I type help.start() in R, it brings up the proper search

I have some data which I am trying to fit with a negative binomial distribution. I have found the glm.nb function from MASS. I have reason to believe that the mean parameter mu depends on certain factors, and that the shape parameter theta depends on others. If, say, the factors are P and Q, it might be that mu ~ P:Q and theta ~ P (where mu ~ P:Q means that mu is a function of the pair (P,Q))

I am having trouble with optim. It claims to have converged to a minimum, yet it has in the course of the optimization visited many points which are closer to optimal. I would be grateful for any explanation of this behaviour. I'm trying to estimate the parameters in the model X ~ Binomial(1,p) * NegBin(mu,theta). So I define a log likelihood function, and invoke optim thus: o <- optim