search for: argchri

This is extremely annoying (and it smells of rat). As of this time (1013 am ET), Google issues the following nasty warning: "This site may harm your computer" when I try to visit any of the CRAN package repository sites or CRAN task view. The funny thing is that Google's Safe Browsing Diagnostic page (it gives diagnostics about any page that it may contain Malware) does not seem

Hi, I noticed whether some one could explain why "&" and "&&" behave differently in data frame transformations. Consider the following : a<-data.frame(r=c(0,0,2,3),g=c(0,2,0,2.1)) Then: > transform(a,R=ifelse(r>0 && g> 0,log(r/g),NA)) r g R 1 0 0.0 NA 2 0 2.0 NA 3 2 0.0 NA 4 3 2.1 NA but > transform(a,R=ifelse(r>0 & g>

Hello, everyone, I have a question about integration of product of two densities. Here is the sample code; however the mean of first density is a function of another random variable, which is to be integrated. ## f=function(x) {dmvnorm(c(0.6, 0.8), mean=c(0.75, 0.75/x))*dnorm(x, mean=0.6, sd=0.15)} integrate(f, lower=-Inf, upper=Inf) ## error message Error in dmvnorm(c(0.6, 0.8), mean = c(0.75,

Hi All, I've been fiddling around with various ways to estimate the popularity of R, SAS, SPSS, Stata, JMP, Minitab, Statistica, Systat, BMDP, S-PLUS, R-PLUS and Revolution R. It's not an easy task. You can see what I've come up with so far at http://r4stats.com/popularity . I'm sure people will have plenty of ideas on how to improve this, so please let me know what you think.

...insert my own coordinates instead of the artificial 3D-pattern, it does not work. It would be great, if anybody could help me! Thanks Pascal [[alternative HTML version deleted]] ------------------------------ Message: 39 Date: Tue, 4 May 2010 17:34:53 +0300 From: Christos Argyropoulos <argchris at hotmail.com> To: <globophobe at gmail.com>, <r-help at r-project.org> Subject: Re: [R] Idiomatic looping over list name, value pairs in R Message-ID: <BLU149-W4751993EF4A405A77558BD8F30 at phx.gbl> Content-Type: text/plain Can you give an example of what the python code i...

If you mean this paper by Fahrmeir: http://biomet.oxfordjournals.org/cgi/content/abstract/81/2/317 I would recommend BayesX: http://www.stat.uni-muenchen.de/~bayesx/. BayesX interfaces with R and estimates discrete (and continuous) time survival data with penalized regression methods. If you are looking for a bona fide Bayesian survival analysis method and do not wish to spend a lot of time

Hello, I was hoping that someone could answer a few questions for me (the background is given below): 1) Can the coxph accept an interaction between a covariate and a frailty term 2) If so, is it possible to a) test the model in which the covariate and the frailty appear as main terms using the penalized likelihood (for gaussian/t frailties) b)augment model 1) by stratifying on the variable that

Hi, You may want to try the double exponential transformation on the numerator and the denominator on this one. The method is described in detail here: http://projecteuclid.org/DPubS?service=UI&version=1.0&verb=Display&handle=euclid.prims/1145474600 If you want to give it a shot outside R there are a couple of C/C++ implementations out there:

Hi, I am trying to "convince" lattice to use bold face in an expression containing Greek characters without any luck. Example code (without Greek characters, renders the expression in bold) library(lattice) data(Cars93,package=="MASS") splom(~Cars93[,5:8]|Origin,data=Cars93,panel=function(x,y,...) { panel.splom(x,y,...)

Goodmorning, This is a documentation related question about the B-spline function in R. In the help file it is stated that: "df degrees of freedom; one can specify df rather than knots; bs() then chooses df-degree-1 knots at suitable quantiles of x (which will ignore missing values)." So if one were to specify a spline with 6 degrees of freedom (and no intercept) then a basis

Hi, I am using GAMs (package mgcv) to smooth event rates in a penalized regression setting and I was wondering if/how one can select the order of the derivative penalty. For my particular problem the order of the penalty (parameter "m" inside the "s" terms of the formula argument) appears to have a larger effect on the AIC/deviance of the estimated model than the