similar to: add a point to regression line and cook's distance

To whom it may concern: Given that my sample size is n, my mean is 100, and my sd is 10, I need to use a random number generator (which I believe is the function rnorm(5,100,10)), but I need to repeat it a large number of times, and then plot the sampling distributions of the sample means, sd's, and variances of those generated sets. I'm having a real hard time trying to figure out how

Hi, I have a nicely printed table of results generated by R's > print(myresult) where myresult is a "data frame". I am trying to put this table into a powerpoint slide for presentation without re-typing and re-formating, i.e., present it as it is in the R window. This saves time when there are a lot of tables to be presented. I tried > sink("myresult.txt") >

I mostly use Windows, but I am slowly learning to use Linux on my second machine. (It came in handy a couple of weeks ago when I had two files to sort, each of length about 2 million. Windows sort died after an hour, but the Linux sorts took 2-3 minutes each.) Anyway the last time I tried installing R in Linux I found out from a helpful computer support person that with my distribution

Hi Community, I'm trying to reconcile Cook's Distances computed in glm. The following snippet of code shows that the Cook's Distances contours on the plot of Residuals v Leverage do not seem to be the same as the values produced by cooks.distance() or in the Cook's Distance against observation number plot. counts <- c(18,17,15,20,10,20,25,13,12) outcome <- gl(3,1,9)

Dear useRs, I have some trouble with the calculation of Cook's distance in R. The formula for Cook's distance can be found for example here: http://en.wikipedia.org/wiki/Cook%27s_distance I tried to apply it in R: > y <- (1:400)^2 > x <- 1:100 > lm(y~x) -> linmod # just for the sake of a simple example >

I have a puzzle as to how R is computing Cook's distance in weighted linear regression. In this case cook's distance should be given not as in OLS case by h_ii*r_i^2/(1-hii)^2 divided by k*s^2 (1) (where r is plain unadjusted residual, k is number of parameters in model, etc. ) but rather by w_ii*h_ii*r_i^2/(1-hii)^2 divided by k*s^2,

The following code demonstrates an annoyance with plot.lm(): library(DAAGxtras) x11(width=3.75, height=4) nihills.lm <- lm(log(time) ~ log(dist) + log(climb), data = nihills) plot(nihills.lm, which=5) OR try the following xy <- data.frame(x=c(3,1:5), y=c(-2, 1:5)) plot(lm(y ~ x, data=xy), which=5) The "Cook's distance" text overplots the label for the point with the

Hi all, Although R seems to have jpeg() and png() functions that converts data into jpeg and png formated files, it doesn't have functions the other way around. Does one of R contributed packages have gif, jpeg and png image readers? I did help.search() but no luck Regards, Jonathan -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read

Dear R experts, Does RMySQL package handle Blob datatype in a MySQL database? Blob can represent an image, a sound or some other large and complex binary objects. In an article published by R-database special interest group, named "A common database interface (DBI)" (updated June 2003), it's mentioned in "open issues and limitations" that "We need to carefully plan

I am introducing the scan() function to my class. Consider the following file (Scanexamp.Rnw ) \documentclass[12pt]{article} \begin{document} <<>>= height = scan() 64 62 66 65 62 69 72 72 70 part = scan(what = character(0)) "Soprano" "Soprano" "Soprano" "Alto" "Alto" "Tenor" "Tenor" "Bass"

I found myself wanting to average a vector [vec] within each level of a factor [Fac], returning a vector of the same length as vec. After a while I realised that lm1 <- lm(vec ~ Fac) fitted(lm1) did what I want. But there must be another way to do this, and it would be good to be able to apply other functions than mean() in this way. Cheers, Murray -- Dr Murray Jorgensen

How do you stop R from putting up a dialog box when you quit Rgui? (I use Windows and I never save workspaces that way) Murray -- Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html Department of Statistics, University of Waikato, Hamilton, New Zealand Email: maj at waikato.ac.nz Fax 7 838 4155 Phone +64 7 838 4773 wk +64 7 849 6486 home

I'm running R 1.2.2 under windows 98 on a Pentium 133 laptop. I can't seem to retrieve the package MASS data sets: > library(MASS) > data(wtloss) Warning message: Data set `wtloss' not found in: data(wtloss) > data(abbey) Warning message: Data set `abbey' not found in: data(abbey) And yet all the .rda files for the MASS datasets are in D:\Program

I want to interlace two vectors. This I can do: > x <- 1:4 > z <- x+0.5 > as.vector(t(cbind(x,z))) [1] 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 but this seems rather inelegant. Any suggestions? Murray -- Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html Department of Statistics, University of Waikato, Hamilton, New Zealand Email: maj at waikato.ac.nz

I'm going to try my hand at converting some Fortran programs to R. Does anyone know of any good articles giving hints at such tasks? I will post a selective summary of my gleanings. Cheers, Murray -- Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html Department of Statistics, University of Waikato, Hamilton, New Zealand Email: maj at waikato.ac.nz

Greetings all. Any help with the following would be appreciated. I want to create a data frame for each file in a directory. The following code does not work but it may show what I am trying to do: carmakes <- c('BMW','Chrysler','Citroen','Fiat','Ford','Holden','Honda',

I got a shock a few days ago when I accidentally visited www.r-project.com . I thought that the r-project site had been hacked until I realised my mistake. There is also a site www.r-project.net. Both of these sites appear to be Japanese. Does anyone know anything about them? I suppose that it is not unusual for names close to those of popular sites to be used. It is good that they use a

Hi, Is there a way to comment out multiple lines at once in R source code like C language's /* */ struct? This is quite useful when one is testing different sections of a source code. Thanks, Jonathan -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info",

Has anyone got a cute way of compiling a table of the available plotting symbols? I've been repeatedly pasting in cno <- cno + 1 cno plot(x,y,pch=cno) which is tedious, and besides I have to note down the symbols by hand. Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html Department of Statistics, University of Waikato, Hamilton, New Zealand Email: maj at

I am exploring the result of clustering a large multivariate data set into a number of groups, represented, say, by a factor G. I wrote a function to see how categorical variables vary between groups: > ddisp <- function(dvar) { + csqt <- chisq.test(G,dvar) + print(csqt$statistic) + print(csqt$observed) + print(round(csqt$expected)) + round(csqt$residuals) + } > > x