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Hi Is it possible to use the rep command (or maybe some other "shortcut") to create a vector with the following format: 4 3 4 2 3 4 1 2 3 4 Any help is much appreciated. Thanks Jacob Jacob L van Wyk Department of Statistics University of Johannesburg, APK Box 524 Auckland Park 2006 South Africa Office Tel: +27 11 559 3080 Fax: +27 11 559 2832 [[alternative HTML version deleted]]

...roup 2. The idea is to study the permutation distribution of mean(group 1) * mean(group2). One way would be to permute 1s and 2s and select the corresponding measurements; calculate the difference in means. Redo this 1000 times, say. Etc. Any help is much appreciated. Thanks Jacob Jacob L van Wyk Department of Statistics University of Johannesburg, APK P O Box 524 Auckland Park 2006 South Africa Tel: +27 11 489 3080 Fax: +27 11 489 2832 [[alternative HTML version deleted]]

...some data in the usual way and making a simple plot, I get the following: Warning message: 'length(rescale)' differs between new and previous ==> NOT changing 'rescale' (This also happens at some other times, doing other things.) Please help. Thank you. Jacob L van Wyk Department of Statistics University of Johannesburg, APK Box 524 Auckland Park 2006 South Africa Office Tel: +27 11 559 3080 Fax: +27 11 559 2832 [[alternative HTML version deleted]]

...been implemented in a R-package, possibly under some sort of assumptions about variances. I would lke my student to apply some regression techniques to data that fit this profile. Any help is much appreciated. (If I have not done my search more carefully - my apologies.) Thanks Jacob Jacob L van Wyk Department of Mathematics and Statistics University of Johannesburg APK P O Box 524 Auckland Park 2006 South Africa Tel: +27-11-489-3080 Fax: +27-11-489-2832

...an't see these accentuated characters: library(RODBC) con <-odbcConnect("trybunal", uid="root", pwd="mypassword") sqlTable(con) the output (abridged) is like that: TABLE_CAT TABLE_SCHEM TABLE_NAME TABLE_TYPE REMARKS 14 trybunal Wyk?adnia innych przepis<f3>w TABLE MySQL instead of <F3> i should see "?" and instead of ? a "?". It is just the same if i use RMySQL instead of RODBC: library(RMySQL) con <-dbConnect(dbDriver("MySQL"), dbname="trybunal", username="r...

...ourse). Can somebody help me to code this efficiently, or elegantly (and smartly) in R, without loops etc. It is intended for first year students that are only starting to learn about statistics (or probability theory), and R of course. Thank you for your time. Regards Jacob Jacob L van Wyk Department of Statistics University of Johannesburg, APK P O Box 524 Auckland Park 2006 South Africa Tel: +27 11 489 3080 Fax: +27 11 489 2832 [[alternative HTML version deleted]]

...sis. Could anybody perhaps assist me in producing a "good" graph in 3d? It probably works in S-Plus, but I am using R. (I have tried plot (locfit object, type="persp") on the ethanol dataset - but this gives a poor result, with a few warnings.) THANK YOU!. Jacob Jacob L van Wyk Department of Statistics University of Johannesburg APK P O Box 524 Auckland Park 2006 South Africa Tel: +27-11-489-3080 Fax: +27-11-489-2832

...n function (perhaps C-code) called "band_den_bin" in the base library (used for kernel density estimators). Is there a newer version of this function. I have an old routine using this but it won't run in the newer version of R. Any help is much appreciated. Jacob Jacob L van Wyk Dept of Statistics University of Johannesburg, APK Campus Box 524 Auckland Park 2006 South Africa [[alternative HTML version deleted]]

...f 3 4 10 2 1 30 4 4 50 How can then get a matrix that looks as follows: 0 0 0 0 30 0 0 0 0 0 0 10 0 0 0 50 I am still learning R. I think reshape will help, but it is not clear how that works here. Any help is much appreciated. Thank you. Jacob Jacob L van Wyk Department of Statistics University of Johannesburg, APK Box 524 Auckland Park 2006 South Africa Office Tel: +27 11 559 3080 Fax: +27 11 559 2832 [[alternative HTML version deleted]]

...Is there a simple way of changing the prompt symbol ">" to, say, "R>" ? (Not just for a temporary session, but every time R command window is opened.) The documentation of doing this is rather "sparse". Much appreciated for your assistance. Jacob Jacob L van Wyk Department of Statistics University of Johannesburg, APK P O Box 524 Auckland Park 2006 South Africa Tel: +27 11 489 3080 Fax: +27 11 489 2832 [[alternative HTML version deleted]]

...plot covers the observed data range only. It appears there is a problem with flim=c(1,6) flim is not actually correct, and consequently c(1,6) is not used correctly. I have also tried to use "xlim=c(1,6)", but without success. I need some help on this please. Thanks Jacob Jacob L van Wyk Department of Statistics University of Johannesburg APK P O Box 524 Auckland Park 2006 South Africa Tel: +27-11-489-3080 Fax: +27-11-489-2832

Sorry for the repeat. The PRESS statistic is defined as sum(y-yhat(i))^2, where yhat(i) denotes the ith predicted value using all the data except the ith case (as used typically in linear models). Thanks again Jacob Jacob L van Wyk Department of Mathematics and Statistics Rand Afrikaans University P O Box 524 Auckland Park 2006 South Africa Tel: +27-11-489-3080 Fax: +27-11-489-2832 ______________________________________ VRYWARING Die...

...as if "proxy authentication required" is causing the problem. It seems I have to set up an .Renviron file, but I am still learning R, and cannot find such a file. Would it help, and how do I create it (it that is a possible alternative to try). Thanks for any comments. Jacob Jacob L van Wyk Department of Statistics University of Johannesburg (APK) PO Box 524, Auckland Park, 2006 Office ph: 011 559 3080 Fax: 011 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://www.uj.ac.za/UJ_email_legal_disclaimer.htm [[alternat...

...annot open: HTTP status was '407 Proxy Authentication Required' I need to tell R that I need a proxy server, and give my proxy settings (how I log onto the server to connect to the Internet. My question is: Where/how do I set this? Any advice is much appreciated. Thank you. Jacob L van Wyk Department of Statistics University of Johannesburg (APK) PO Box 524, Auckland Park, 2006 Office ph: 011 559 3080 Fax: 011 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://www.uj.ac.za/UJ_email_legal_disclaimer.htm [[alternat...

...r message displayed in R: R> source(.trPaths[5], echo=TRUE, max.deparse.length=150) Error in source(.trPaths[5], echo = TRUE, max.deparse.length = 150) : object '.trPaths' not found Can somebody please help me solve this. Thank you so much for your time. Regards Jacob Jacob L van Wyk, Dept. of Statistics, University of Johannesburg (APK), Box 524, Auckland Park, 2006, South Africa Office: +27 11 559 3080, Fax: +27 11 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://disclaimer.uj.ac.za [[alternative HTML v...

...studentized intervals? Another question: How then can I compute the studentized intervals without physically doing a double bootstrap. Does the function use a "nonparametric delta mathod"? Any help is much appreciated. I have probably overlooked something? Thank you. Jacob Jacob L van Wyk, Dept. of Statistics, University of Johannesburg (APK), Box 524, Auckland Park, 2006. Office: +27 11 559 3080, Fax: +27 11 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://www.uj.ac.za/UJ_email_legal_disclaimer.htm [[alternat...

...2 <- seq(0,1,.01) f2 <- 0.5*(x2^2) x3 <- seq(1,2,.01) f3 <- (2*x3)-(0.5*(x3^2))-1 x4 <- seq(2,3,.01) f4 <- rep(1,101) x <- c(x1,x2,x3,x4) F <- c(f1,f2,f3,f4) plot(x,F,type='l') But this seems very cumbersome. Any help is much appreciated. Thanks Jacob Jacob L van Wyk Department of Statistics University of Johannesburg APK P O Box 524 Auckland Park 2006 South Africa Tel: +27-11-489-3080 Fax: +27-11-489-2832

...and select "Set CRAN mirror". I choose one, but the R comes back with the following: R> chooseCRANmirror() Error in m[, 1L] : incorrect number of dimensions Could you possibly think of a fix for this problem? (Maybe I should try setting System variables?) Thanks Jacob Jacob L van Wyk Department of Statistics University of Johannesburg (APK) PO Box 524, Auckland Park, 2006 Office ph: 011 559 3080 Fax: 011 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://www.uj.ac.za/UJ_email_legal_disclaimer.htm [[alternat...

Hallo I am teaching a very elementary intro course about R, and want to show the students how to find the distribution of the maximum of rolling two balanced die. Is there perhaps a more elegant way to do this, other than the way I am using below? (I would like to show them two ways - the one shown here, and perhaps and improved/elegant approach (showing off the "beauty" of R.

...x(y))) lines(x, y, lty = 2) THANKS FOR ANY ASSISTANCE. ps: This code differs from that in the book. I have tried both, without success. Even if I just use, for example, fit1 <- locfit( ~ claw54, deg = 0, kern = "gauss", alpha = c(0, 0.315)) I do not get the same result. Jacob L van Wyk, Dept. of Statistics, University of Johannesburg (APK), Box 524, Auckland Park, 2006. Office: +27 11 559 3080, Fax: +27 11 559 2499 ________________________________ This email and all contents are subject to the following disclaimer: http://www.uj.ac.za/UJ_email_legal_disclaimer.htm [[alternat...