similar to: Variable Importance - Random Forest

I am trying to use the random forests package for classification in R. The Variable Importance Measures listed are: -mean raw importance score of variable x for class 0 -mean raw importance score of variable x for class 1 -MeanDecreaseAccuracy -MeanDecreaseGini Now I know what these "mean" as in I know their definitions. What I want to know is how to use them. What I am trying to

HI, Dear Andy, I run the RandomFOrest in R, and get the following resutls in variable importance: What is the meaning of MeanDecreaseAccuracy and MeanDecreaseGini? I found they are raw values, they are not scaled to 1, right? Which column if most similar to the variable rel.influence in Boosting? Thanks so much! > fit$importance 0 1

Hi All, In the script below, the importance measure for column 4 (ie MeanDecreaseGini) indicated "Inf" for V7. Running the getTree command showed that "V7" had been selected at least twice in one of the trees for Random Forest. So the "Inf" command was not generated as a result of dividing the sum of the decreases by 0. Any suggestions on what may be causing the

Hello, I am using the R randomForest package to classify variable stars. I have a training set of 1755 stars described by (too) many variables. Some of these variables are highly correlated. I believe that I understand how randomForest works and how the variable importance are evaluated (through variable permutations). Here are my questions. 1) variable importance error? Is there any ways

For anyone who is knowledgeable about the randomForest package in R, I have a question: When I look at the variable importance for data, I see that my response variable is included along with my predictor variables. That is, I am getting a MeanDecreaseGini for my response variable, and therefore it seems as though it is being treated as a predictor variable. my code (just in case it helps) :

Dear List, can anyone explain me this result (Windows XP, R 2.0.1): > (0.2-0.1)==0.1 [1] TRUE > (0.3-0.2)==0.1 [1] FALSE Regards, Ralf Strobl

Dear R Developers I'm using the great randomForest package (4.6-7) for many projects and recently stumbled upon a problem when I wrote unit tests for one of my projects: On Windows, there are small numeric deviations when using the 32- / 64-bit version of R, which doesn't seem to be a problem on Linux or Mac. R64 on Windows produces the same results as R64/R32 on Linux or Mac: >

Emanuel Strobl wrote: > Am Dienstag, 18. Januar 2005 16:17 schrieb Andrew L. Neporada: > > On Tue, Jan 18, 2005 at 01:06:43PM +0100, Emanuel Strobl wrote: > > > Dear experts, > > > > > > I have two USB-RS232 Adaptors, both with PL2303 chipset. One is working > > > the other one not (I hate to say it but both are working under win). > > > >

Hi, I'm using package "caret" to rank predictors using random forest model and draw predictors importance plot. I used below commands: rf.fit<-randomForest(x,y,ntree=500,importance=TRUE) ## "x" is matrix whose columns are predictors, "y" is a binary resonse vector ## Then I got the ranked predictors by ranking

I sent a note about this a couple of weeks ago, but have not heard anything. I'm really getting a bit desperate. I have a system that I am trying to upgrade from 8.2 to 9.0. I have built it and installed the kernel, but it fails to boot. The boot freezes after probing for my hard drives during the probe of the CDROM. It just sits there, seemingly forever, though I have never waited longer

Hi, i'm new on sieve, but want to use ist with sogo. The Problem is, that when i set a redirect or vacation rule like: redirect "email at example.com"; (real Adress is different) the sieve says the mail would be forwarded, but no mail is sent. (No Action in /var/log/maillog) And because there is no Error-Message it's difficult to search for... Dovecot log ------- Jan 28

Full_Name: Anne-Laure Boulesteix Version: 1.6.0 OS: Linux Submission from: (NULL) (141.84.161.156) Hi, I noticed the following problem with 1.6.0 (which was not present in 1.5.1): I work with very large datasets and encountered a problem with memory allocation, (probably a memory leak). I wrote a programm with a loop. In this loop in each iteration I create a very large matrix and assign

Hello, I would like to reshape my data for presentation purposes from something like this: > test <- data.frame(a=c("A","A","A","A","B","B","B"),b=c(1,1,2,2,1,1,1),c=1:7) > test a b c 1 A 1 1 2 A 1 2 3 A 2 3 4 A 2 4 5 B 1 5 6 B 1 6 7 B 1 7 to something like this: a b c 1 A 1 1,2 3 A 2 3,4 5 B 1 5,6,7 This seems

Hello, I would like to calculate the 95% confidence intervals for the estimates of a linear model and I just wanted to check that I am doing it correct. Is it just: Estimate + 1.95996*Std.Error to Estimate - 1.95996*Std.Error or is there another approach that doesn't assume a normal distrbution? Thanks. Apologies for my naiivity Dan --

Dear best guys, I really love 5.3 in many ways but here're some unbelievable transfer rates, after I went out and bought a pair of Intel GigaBit Ethernet Cards to solve my performance problem (*laugh*): (In short, see *** below) Tests were done with two Intel GigaBit Ethernet cards (82547EI, 32bit PCI Desktop adapter MT) connected directly without a switch/hub and "device

Hi, I am trying to produce a plot with an xlabel that reads (x >= 5%) with the >= turned into the correct epression. I can do this up to the percentage sign by specifiing xlab=expression(x>=5). Whatever I do to include the % sign as well doesn't seem to work. xlab=bquote(x>=5.("%")) almost works but includes brackets. Anyonw know how to solve this one Dan PS I am

Hello, I would like to scrape some html tables from a web page and convert them to a data.frame so I can perform further analysis. Could anyone tell me the best way to do this? Would it be more appropriate to use an external tool first? Thanks Dan -- ************************************************************** Daniel Brewer, Ph.D. Institute of Cancer Research Molecular Carcinogenesis

Hello, I have a data.frame like this: a 1,2,3,4 b1 b 6,7 b3 And I would like to transform it to this: a 1 b1 a 2 b1 a 3 b1 a 4 b1 b 6 b3 b 7 b3 I have been looking at ddply but can't seem to work it out. ANy help would be gratefully received. Dan -- ************************************************************** Daniel Brewer, Ph.D. Institute of Cancer Research Molecular Carcinogenesis

Hello, I have a data.frame which I would like to sort with the primary key decreasing while the secondry key is increasing e.g. x <- data.frame(One=c(1,1,1,2,2,3,4,5),Two=c(2,3,1,2,3,3,3,3)) I would like to order it so it looks like this: One Two 8 5 3 7 4 3 6 3 3 4 2 2 5 2 3 3 1 1 1 1 2 2 1 3 i.e. primarily decreasing in the 1st column but if there is a

Hello, I have a gene expression matrix with columns being samples and rows being genes. I would like to display the expression values for each gene. I have two groups which I colour differently. The aim is to see if there is any difference between the two groups consistently across genes. So the following works well: