similar to: variable/model selction (step/stepAIC) for biglm ?

Hello dear R-help members, I recently became interested in using biglm with leaps, and found myself somewhat confused as to how to use the two together, in different settings. I couldn't find any example codes for the leaps() package (except for in the help file, and the examples there are not as rich as they could be). That is why I turn to you in case you could share some good tips and

Hello. I had been struggling with running linear regression using lm() primarily because my data has a few categorical variables with at least a thousand levels. I tried the biglm() function and it worked. My problem now is that i don't know how to get the R2 results. Could someone help? Thanks, sean

Hello dear R-help group. My task looks simple, but I can't seem to find a "smart" (e.g: non loop) solution to it. Task: I wish to randomize a data.frame by one column, while keeping the inner-order in the second column as is. So for example, let's say I have the following data.frame: xx <-data.frame(a= c(1,2,2,3,3,3,4,4,4,4) , b =

Hello R help members. I came across today with an article on Barnard's exact test (http://www.cytel.com/Papers/twobinomials.pdf), that is supposed to give a more powerful fisher.test - Because it doesn't assume that we know the row and column totals are in advance. Any pointers to such a function ? Thanks, Tal -- ---------------------------------------------- My contact information:

*(note*: This is an R community question, not a statistical nor coding question. Since this is my first time writing such a post, I hope no one will take offence of it.) Hello all, I will be attending useR 2009 next week, and was wondering if there are any of you who are *bloggers *intending to participate and report on useR 2009? If so - I would love to know your blogs URL so as to follow you.

Hello Martin Maechler and All, A simple question (I hope): How can I compute the "sum of the dissimilarities" that appears in the pam command (from the cluster package) ? Is it the "manhattan" distance (such as the one implemented by "dist") ? I am asking since I am running clustering on a dataset. I found 7 medoids with the pam command, and from it I have the

Hello all. I wish to run k-means with "manhattan" distance. Since this is not supported by the function "kmeans", I turned to the "pam" function in the "fpc" package. Yet, when I tried to have the algorithm run with different starting points, I found that pam ignores and keep on starting the algorithm from the same starting-points (medoids). For my

(I use R 2.9.1 with win XP) If I run this code: seq(-0.1,.9, by = .05)[seq(-0.1,.9, by = .05) <= 0.5] I get this output: [1] -0.10 -0.05 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 Why is 0.50 not in the results ? (It seems that it gives a slightly bigger number then 0.5 but I don't understand why it does that) Where as if I try: seq(-0.1,.9, by = .05)[seq(-0.1,.9, by = .05) <=

Hello dear R-help group (and David Smith from REvolution), I would like to perform parallel computing using R with Condor (hopefully using foreach or other recommended solutions, if available) for some "Embarrassingly parallel" problem. I will start by listing what I found so far, and then go on asking for help. So far I found the a manual by Xianhong Xie from Rnews_2005-2 (see page

Hello all. I wish to read a large data set into R. My current issue is in getting the data so that R would be able to access it. Using read.table won't work since the data is over 1GB in size (and I am using windows XP), so my plan was to read the file chunk by chunk and each time move it into bigmemory (I'll play with that when the time will come, maybe ff is better ?!). I encountered

Hello all, I wish to perform a mcnemar test for a 3 by 3 matrix. By running the slandered R command I am getting a result but I am not sure I am getting the correct one. Here is an example code: (tt <- as.table(t(matrix(c(1,4,1 , 0,5,5, 3,1,5), ncol = 3)))) mcnemar.test(tt, correct=T) #And I get: McNemar's Chi-squared

Hello dear R members. I have been learning the Anova syntax in order to perform an SS type III Anova with repeated measures designs (thank you Prof. John Fox!) And another question came up: where/what are the (between/within) residuals for my model? ############ Play code: phase <- factor(rep(c("pretest", "posttest", "followup"), c(5, 5, 5)),

Hello dear R help group, I would like to download the tRNA data on: http://gtrnadb.ucsc.edu/download.html And then import it into R. Can anyone direct me as to how to do so? Thanks, Tal ---------------------------------------------- My contact information: Tal Galili E-mail: Tal.Galili@gmail.com Phone number: 972-52-7275845 FaceBook: Tal Galili My Blogs: http://www.talgalili.com (Web and

Hello dear R help group. My question is statistical and not R specific, yet I hope some of you might be willing to help. *Experiment settings*: We have a list of subjects. each of them went through two tests with the answer to each can be either 0 or 1. *Goal*: We want to know if the two experiments yielded different results in the subjects answers. *Statistical test (and why it won't

Hello people, A while back I wanted to plot boxplots with interactions that will have a dot for the mean of the sample + bars for the SE. After searching for some code, I found something that did it for one level, but couldn't find something that will allow for interactions the way the original boxplot does. After playing with the original code, I found a way for allowing the boxplot code to

Hello. I am looking for a way to add table values (from a "table" object) into a mosaic plot of that table (which is produced by the "mosaicplot" command on the table object). The only reference I was successful in finding on the web was in a script here: http://tables2graphs.com/doku.php?id=03_descriptive_statistics#figure_2

After reading more, I understand I didn't formulate my last question correctly, so please allow me to rephrase: What I am looking for is a way to save the R console session output. That is, a command that would combine the results of using: ?sink # And ?savehistory My motivation for this is that doing it will allow someone who is a blind user of R to be able to easily export his results to

Hello dear R-help group. I wish to plot a scatter plot using icons (or images) instead of points. Is it possible? and how so? Thanks, Tal ---------------------------------------------- My contact information: Tal Galili E-mail: Tal.Galili@gmail.com Phone number: 972-52-7275845 FaceBook: Tal Galili My Blogs: http://www.talgalili.com (Web and general, Hebrew) http://www.biostatistics.co.il

Hi dear R help group. I was wondering how can I find out which CRAN mirror would be the fastest for me (I leave in Israel and therefore don't have a CRAN mirror for our country to go to by default) Thanks, Tal -- ---------------------------------------------- My contact information: Tal Galili Phone number: 972-50-3373767 FaceBook: Tal Galili My Blogs: http://www.r-statistics.com/

Hello all I wish to perform a mcnemar.test() for a 5X5 matrix. Wikipedia tells me (http://en.wikipedia.org/wiki/Cochran_test) I should turn to cochran.test. The only place I found it was in the "outliers" package, but the command cochran.test() acts differently then mcnemar.test() , and doesn't take a table as input. Any ideas on how to use it ? #Example code: aa =