similar to: Matrix

Please can you help me I have the following problem: I have selected an lm model through the step procedure which visualize for each step the AIC value; then I have calculated for the initial model and the selected one the AIC using the funnction AIC. The results are different.What's happened? Emilia Rocco Dipartimento di Statistica "G. Parenti" Università di Firenze e-mail:

Dear All, I'm trying to maximize a likelihood with respect one parameter using "optimize" on simulated data (without error component). I've iterated the maximization procedure 1000 times and I should always obtain the same estimate of the parameter (equal to the simulated one) but, instead, i obtain different results (the likelihood function shouldn't be flat). Does

Hello R-Users, I have to invert a matrix 3000X3000 and the solve method doesn't work or it is too slow. Are there any methods to invert a big matrix? Regards Stefan --------------------------------- [[alternative HTML version deleted]]

Dear R users since R 2.6.0 when I try to save a graph from the Rgraphic device I find that the system becomes so slow that I'm forced to kill the process. This usually does not happen at the beginning of the session. The problem seems to arise when the system opens the dialog window to choose the directory and file name. (R version 2.6.1 under Windows XP) Thank you all Giovanni --

Dear All, I am in the somewhat unfortunate position of having to reproduce the results previously obtained from (non-metric?) MDS on a "kinship" matrix using Statistica. A kinship matrix measures affinity between groups, and has its maximum values on the diagonal. Apparently, starting with a nxn kinship matrix, all it was needed to do was to feed it to Statistica flagging that the

Hi, I have a problem concerning discrepances between R (which I use) and Statistica (which uses my supervisor). I can't say what is the origin of these differences but unfortunately my supervisor doesn't know that either. Our response variable is number (or presence/absence) of parasites in rodents and explanatory variables are presence/absence of several alleles. The rodents were

I am a new R user attempting to convert files from Statistica to R. I can export from Statistica to SPSS .por format, but not to the SPSS .sav format. Is there a procedure for easily accomplishing this, which will allow me to keep variable short and long labels (big surveys LOTS of time to replace all this work). Many thanks for sharing your time and knowledge. steve Dr Steven M Burgess

Hi everybody, I would like to compute the mean for 1 variable between the rows with the same levels. For example, with the dataset below: Factor1 Factor2 Value A X 1 A X 2 A Y 3 A Y 4 B X 5 B X 6 B Y

Hello, I am a new R user and trying to learn how to implement the mahalanobis function to measure the distance between to 2 population centroids. I have used STATISTICA to calculate these differences, but was hoping to learn to do the analysis in R. I have implemented the code as below, but my results are very different from that of STATISTICA, and I believe I may not have interpreted the help

Hi, Sorry to bother you again. I would like to estimate the effect of several categorical factors (two between subjects and one within subjects) on two continuous dependent variables that probably covary, with subjects as a random effect. *I want to control for the covariance between those two DVs when estimating the effects of the categorical predictors** on those two DVs*. The thing is, i

Hi there, I had written a library under R 1.9.0 and now I would like to import that library under R 2.0.1 Apparently it does not work; I can install the package, but when I try to read it the error is the following: Error in library(compvar) : 'compvar' is not a valid package -- installed < 2.0.0 I have checked other libraries in R 2.0.1 and I noticed that there is a new folders

Given this example #start code a<-c(0,70,50,100,70,650,1300,6900,1780,4930,1120,700,190,940, 760,100,300,36270,5610,249680,1760,4040,164890,17230,75140,1870,22380,5890,2430) b<-c(0,0,10,30,50,440,1000,140,70,90,60,60,20,90,180,30,90, 3220,490,20790,290,740,5350,940,3910,0,640,850,260) wilcox.test(a, b, paired=FALSE) #sum of rank for first sample sum.rank.a <-

Hi STATISTICA has a function called "Two-way joining" (see http://www.statsoft.com/TEXTBOOK/stcluan.html#twotwo) and the reference material states that this is based on the method as published by Hartigan (found this paper: http://www.jstor.org/pss/2284710 through wikipedia). What is the relationship (if any) between the "heatmap" function in R and this technique? Is there an

Hello, I have done a scatterplot and now would like to add its regression line but it does not show. Below, the code I have used. lm3 <- lm(data$S_pH_KCl2.5_BCx~data$B_OleicoPF_BCx_per) plot(data$S_pH_KCl2.5_BCx, data$B_OleicoPF_BCx_per) abline(lm3) I have been able to do the complete operation using the software STATISTICA but it would be great to do it with R. If you require more details

Probably, it's an obvious info, but I have not found anything in R FAQ concerning this feature/bug. The results of ks.test and wilcoxon.test (in the Mann-Whitney version, paired = 'FALSE') don't coincide with the results from the other statistical packages, e.g. Statistica, Medcalc, and (as for MW test) from the numerous online MW tests. E.g. Statistica p-value=0.0435353 Medcalc

Hi everybody, I am starting my friendship with R. Now I want to do a Correspondence Analysis using the vegan library or multiv library. Both give me the same results which differ from the ones I get running other programs like Statistica... I wounder if there is a problem with my matrix. I have cualitataive variable in the columns and sampling units in the rows... I import my matrix into R

Dear R gurus I am analysing data from a study of behaviour and shade utilization of chimpanzees. I am using GLMs in R (version 2.13.0) to test whether shade/sun utilization is predicted by behaviour observed. I am thus interested in whether an interaction of behaviour (as a predictor) and presence in the sun/shade (also predictor) predicts the counts I have for the respective categories. I have

Dear R users I recently migrated from Statistica/SigmaPlot (Windows) to R (Linux), so please excuse if this may sound 'basic'. When running a nonlinear regression (V = Vmax * conc / (Ks + conc), i.e. Michaelis-Menten) on SigmaPlot, I get the output listed below: >>>Begin SigmaPlot Output<<< R = 0.94860969 Rsqr = 0.89986035 Adj Rsqr = 0.89458984 Standard Error of

Dear R-users, I used to give commands such as: > source(file="~/path/to/file.R", chdir=TRUE) but with the latest v. 2.1.0 it does not seem to work anymore. I tried to figure out what it was going on and it seems that the string for which > class(file) [1] "character" is changed to > class(file) [1] "file" "connection" when the connection is

I am new to using R and would appreciate some advice on which books to start with to get up to speed on using R. My Background: 1-C# programmer. 2-Programmed directly using IMSL (Now Visual Numerics). 3- Used in past SPSS and Statistica. I put together a list but would like to pick the "best of" and avoid redundancy. Any suggestions on these books would be helpful (i.e. too much