similar to: Tukey's biweight

Hello, I'm trying to do a little rlm of some data that looks like this: UNIT COHORT perdo adjodds 1010 96 0.39890 1.06894 1010 97 0.48113 1.57500 1010 98 0.36328 1.21498 1010 99 0.44391 1.38608 It works fine like this: rlm(perdo ~ COHORT, psi=psisquare) But the problem is that I have about 100 UNITs, and I want to do a

Dear Group, I am having trouble with using rlm on multivariate data sets. When I call rlm I get Error in lm.wfit(x, y, w, method = "qr") : incompatible dimensions lm on the same data sets seem to work well (see code example). Am I doing something wrong? I have already browsed through the forums and google but could not find any related discussions. I use Windows XP and R

I have data on every grade in all elementary schools in Chicago over 5 years. I would like to estimate a trend over time for each grade in each school. There are 17,600 data all together (about 460 schools, nearly 8 grades each, over 5 years). Is there a not-so-hard way to do this in R (I was thinking of using rlm)? ______________________________________________________________________ Stuart

How do we get 2-tailed p-values for the rlm summary? I'm using the following: > fit <- rlm(oatRT ~ oatoacData$erp, psi=psi.bisquare, maxit=100, na.action='na.omit') > fitsum <- summary(fit, cor=F) > print(fitsum) Call: rlm(formula = oatRT ~ oatoacData$erp, psi = psi.bisquare, maxit = 100, na.action = "na.omit") Residuals: Min 1Q Median

R-experts, I have fitted many different lines. The fast-tau estimator (yellow line) seems strange to me?because this yellow line is not at all in agreement with the other lines (reverse slope, I mean the yellow line has a positive slope and the other ones have negative slope). Is there something wrong in my R code ? Is it because the Y variable is 1 vector and should be a matrix ? Here is the

You need to pay attention to the documentation more closely. If you don't know what something means, that is usually a signal that you need to study more... in this case about the difference between an input variable and a design (model) matrix. This is a concept from the standard linear algebra formulation for regression equations. (Note that I have never used RobPer, nor do I regularly

On 31/03/2018 11:57 AM, varin sacha via R-help wrote: > Dear R-experts, > > Here below my reproducible R code. I want to add many straight lines to a plot using "abline" > The last fit (fast Tau-estimator, color yellow) will not appear on the plot. What is going wrong ? > Many thanks for your reply. > It's not quite reproducible: you forgot the line to create

Dear R-experts, Here below my reproducible R code. I want to add many straight lines to a plot using "abline" The last fit (fast Tau-estimator, color yellow) will not appear on the plot. What is going wrong ? Many thanks for your reply. ########## Y=c(2,4,5,4,3,4,2,3,56,5,4,3,4,5,6,5,4,5,34,21,12,13,12,8,9,7,43,12,19,21)

I want to leave a little extra room at the bottom for a legend in a box plot, but I find that the boxplot function ignores ylim. Is there any way around this? Thanks. ______________________________________________________________________ Stuart Luppescu -=-=- University of Chicago $(B:MJ8$HCRF`H~$NIc(B -=-=- s-luppescu at uchicago.edu

Is the width= parameter in barplot() supposed to work? I couldn't get it to work in my plot, and even in the example, data(VADeaths, package = "base") barplot(VADeaths, width=rep(0.1, 4)) the plot looks identical regardless of what I put in for the width. I looked at the source for barplot() and it looks like it SHOULD work (but what do I know). Am I doing something wrong?

Is there an efficient way to do linear model selection by choosing the model with the highest BIC from all possible models? ______________________________________________________________________ Stuart Luppescu -=-=- University of Chicago $(B:MJ8$HCRF`H~$NIc(B -=-=- s-luppescu at uchicago.edu http://www.consortium-chicago.org/people/sl.html http://musuko.uchicago.edu/pubkey.asc

I would like to make my horizontal barplot vertical axis labels perpendicular to the axis. I tried las=1, srt=90; I even tried yaxt='n' thinking I'd put the labels in using mtext, but the axis continued to be drawn. Can anyone help me with this? My barplot() statement looks like this: barplot(height=foo$rebint[o1], names=foo$Unit[o1], horiz=TRUE, col=mycolors[foo$type[o1]],

I'm stumped with this. When I execute the lines in the function singly, they run fine, but when I run the function, I get this error on the read.table() line: Error in count.fields(file, sep, quote, skip) : can't open file fspci1.dat Can anyone tell my why this should be so? Here is the program: library(rpart) wait <- function(str="Press a key when ready...")

Has the loess.smooth() function changed? It used to work, but now it causes R to abort with a segmentation fault. I stole the function points.lines() from V&R 1st ed. pp. 67--68, but now it only works if I remove the line with loess.smooth. Here's the function I'm using: points.lines <- function(x, y, ...) { cor1 <-round(cor(x, y, use="pairwise"), digits=2)

I need to calculate an index of predictive association, similar to Goodman and Kuskal's (1954) for a 2x2x2 array. I have two questions: 1) Is there an easy way to do this in R? (Of course, the answer to this kind of question is nearly always ``yes.'' Perhaps I should have asked, ``How can I do this in R?'') 2) Is it reasonable to try this with a 3-dimensional array? The way I

I would like to make the print format of the axis value labels appear as ``nn%'' instead of just the numbers. Is there a way to do this? Also, the x axis value labels on my horizontal barplot are rotated 90 degrees (perpendicular to the axis) no matter what I do. I tried las=1 but that didn't work. Is this doable? Thanks. $platform [1] "i686-pc-linux-gnu" $arch [1]

I have plain-text data in lower triangular form that I want to read in. Does anyone know of an easy way to do this? ______________________________________________________________________ Stuart Luppescu -=-=- University of Chicago $(B:MJ8$HCRF`H~$NIc(B -=-=- s-luppescu at uchicago.edu http://www.consortium-chicago.org/people/sl.html http://musuko.uchicago.edu/pubkey.asc for PGP

I am needing some expertise with regard to the S-Plus command lmRobMM and its R counterpart rlm(formula,data,method="MM") I have used lmRobMM(formula,data) in S-Plus on the Stackloss data and obtained for my residuals 6.217777 1.150717 6.427946 8.174019 -0.6713005 -1.248641 -0.4236203 0.5763797 -1.057899 0.3593823 11 12 13 14 15 16

I seem to remember this coming up before, but I can't find it any messages I've saved or in the archives (searching by subject). I want to rotate mtext so that it's perpendicular to the right side. I tried srt=90 and lots of other values, but it seems to be ignored. Is there a way to do this? ______________________________________________________________________ Stuart Luppescu

This is really a question of how to program this *BETTER*. It works as I have done it, but is quite ugly. I want to do a 3d scatterplot of the upper triangle of a matrix, where the z-values are the values in the matrix, and the row and column indices are the y- and x-values. The complete (11 by 11) matrix is mmtop94.2. Here is my awkward code: mmtop94.2[lower.tri(mmtop94.2)] <- NA # Here i