Displaying 20 results from an estimated 4000 matches similar to: "RandomForest & memory demand"
2008 Jun 15
1
randomForest, 'No forest component...' error while calling Predict()
Dear R-users,
While making a prediction using the randomForest function (package
randomForest) I'm getting the following error message:
"Error in predict.randomForest(model, newdata = CV) : No forest component
in the object"
Here's my complete code. For reproducing this task, please find my 2 data
sets attached ( http://www.nabble.com/file/p17855119/data.rar data.rar ).
2012 Mar 08
2
Regarding randomForest regression
Sir,
This query is related to randomForest regression using R.
I have a dataset called qsar.arff which I use as my training set and
then I run the following function -
rf=randomForest(x=train,y=trainy,xtest=train,ytest=trainy,ntree=500)
where train is a matrix of predictors without the column to be
predicted(the target column), trainy is the target column.I feed the same
data
2009 Dec 10
2
different randomForest performance for same data
Hello,
I came across a problem when building a randomForest model. Maybe someone can help me.
I have a training- and a testdataset with a discrete response and ten predictors (numeric and factor variables). The two datasets are similar in terms of number of predictor, name of variables and datatype of variables (factor, numeric) except that only one predictor has got 20 levels in the training
2012 Oct 22
1
random forest
Hi all,
Can some one tell me the difference between the following two formulas?
1. epiG.rf <-randomForest(gamma~.,data=data, na.action = na.fail,ntree =
300,xtest = NULL, ytest = NULL,replace = T, proximity =F)
2.epiG.rf <-randomForest(gamma~.,data=data, na.action = na.fail,ntree =
300,xtest = NULL, ytest = NULL,replace = T, proximity =F)
[[alternative HTML version deleted]]
2010 May 05
1
What is the default nPerm for regression in randomForest?
Could not find it in ?randomForest.
Thank you for your help!
--
Dimitri Liakhovitski
Ninah.com
Dimitri.Liakhovitski at ninah.com
2006 Jul 26
3
memory problems when combining randomForests
Dear all,
I am trying to train a randomForest using all my control data (12,000 cases, ~
20 explanatory variables, 2 classes). Because of memory constraints, I have
split my data into 7 subsets and trained a randomForest for each, hoping that
using combine() afterwards would solve the memory issue. Unfortunately,
combine() still runs out of memory. Is there anything else I can do? (I am not
using
2006 Jul 27
2
memory problems when combining randomForests [Broadcast]
You need to give us more details, like how you call randomForest, versions
of the package and R itself, etc. Also, see if this helps you:
http://finzi.psych.upenn.edu/R/Rhelp02a/archive/32918.html
Andy
From: Eleni Rapsomaniki
>
> Dear all,
>
> I am trying to train a randomForest using all my control data
> (12,000 cases, ~ 20 explanatory variables, 2 classes).
> Because
2004 Jan 20
1
random forest question
Hi,
here are three results of random forest (version 4.0-1).
The results seem to be more or less the same which is strange because I
changed the classwt.
I hoped that for example classwt=c(0.45,0.1,0.45) would result in fewer
cases classified as class 2. Did I understand something wrong?
Christian
x1rf <- randomForest(x=as.data.frame(mfilters[cvtrain,]),
2006 Jul 24
2
RandomForest vs. bayes & svm classification performance
Hi
This is a question regarding classification performance using different methods.
So far I've tried NaiveBayes (klaR package), svm (e1071) package and
randomForest (randomForest). What has puzzled me is that randomForest seems to
perform far better (32% classification error) than svm and NaiveBayes, which
have similar classification errors (45%, 48% respectively). A similar
difference in
2004 Apr 15
7
all(logical(0)) and any(logical(0))
Dear R-help,
I was bitten by the behavior of all() when given logical(0): It is TRUE!
(And any(logical(0)) is FALSE.) Wouldn't it be better to return logical(0)
in both cases?
The problem surfaced because some un-named individual called randomForest(x,
y, xtest, ytest,...), and gave y as a two-level factor, but ytest as just
numeric vector. I thought I check for that in my code by testing
2003 Aug 20
2
RandomForest
Hello,
When I plot or look at the error rate vector for a random forest
(rf$err.rate) it looks like a descending function except for a few first
points of the vector with error rates values lower(sometimes much lower)
than the general level of error rates for a forest with such number of trees
when the error rates stop descending. Does it mean that there is a tree(s)
(that is built the first in
2012 Dec 03
2
Different results from random.Forest with test option and using predict function
Hello R Gurus,
I am perplexed by the different results I obtained when I ran code like
this:
set.seed(100)
test1<-randomForest(BinaryY~., data=Xvars, trees=51, mtry=5, seed=200)
predict(test1, newdata=cbind(NewBinaryY, NewXs), type="response")
and this code:
set.seed(100)
test2<-randomForest(BinaryY~., data=Xvars, trees=51, mtry=5, seed=200,
xtest=NewXs, ytest=NewBinarY)
The
2023 May 09
1
RandomForest tuning the parameters
Hi Sacha,
On second thought, perhaps this is more the direction that you want ...
X2 = cbind(X_train,y_train)
colnames(X2)[3] = "y"
regr2<-randomForest(y~x1+x2, data=X2,maxnodes=10, ntree=10)
regr
regr2
#Make prediction
predictions= predict(regr, X_test)
predictions2= predict(regr2, X_test)
HTH,
Eric
On Tue, May 9, 2023 at 6:40?AM Eric Berger <ericjberger at gmail.com>
2013 Feb 03
3
RandomForest, Party and Memory Management
Dear All,
For a data mining project, I am relying heavily on the RandomForest and
Party packages.
Due to the large size of the data set, I have often memory problems (in
particular with the Party package; RandomForest seems to use less memory).
I really have two questions at this point
1) Please see how I am using the Party and RandomForest packages. Any
comment is welcome and useful.
2005 Oct 11
1
a problem in random forest
Hi, there:
I spent some time on this but I think I really cannot figure it out, maybe I
missed something here:
my data looks like this:
> dim(trn3)
[1] 7361 209
> dim(val3)
[1] 7427 209
> mg.rf2<-randomForest(x=trn3[,1:208], y=trn3[,209], data=trn3, xtest=val3[,
1:208], ytest=val3[,209], importance=T)
my test data has 7427 observations but after prediction,
> dim(mg.rf2$votes)
2009 Apr 07
1
Concern with randomForest
Hi all,
When running a randomForest run using the following command:
forestplas=randomForest(Prev~.,data=plas,ntree=200000)
print(forestplas)
I get the following result:
Call:
randomForest(formula = Prev ~ ., data = plas, ntree = 2e+05,
importance = TRUE)
Type of random forest: regression
Number of trees: 2e+05
No. of variables tried at each split: 5
2010 May 25
1
Need Help! Poor performance about randomForest for large data
Hi, dears,
I am processing some data with 60 columns, and 286,730 rows.
Most columns are numerical value, and some columns are categorical value.
It turns out that: when ntree sets to the default value (500), it says "can
not allocate a vector of 1.1 GB size"; And when I set ntree to be a very
small number like 10, it will run for hours.
I use the (x,y) rather than the (formula,data).
2008 Dec 26
2
about randomForest
hello,
I want to use randomForest to classify a matrix which is 331030?42,the last column is class signal.I use ?
Memebers.rf<-randomForest(class~.,data=Memebers,proximity=TRUE,mtry=6,ntree=200) which told me" the error is matrix(0,n,n) set too elements"
then I use:
Memebers.rf<-randomForest(class~.,data=Memebers,importance=TRUE,proximity=TRUE) which told me"the error is
2011 Sep 07
1
randomForest memory footprint
Hello, I am attempting to train a random forest model using the
randomForest package on 500,000 rows and 8 columns (7 predictors, 1
response). The data set is the first block of data from the UCI
Machine Learning Repo dataset "Record Linkage Comparison Patterns"
with the slight modification that I dropped two columns with lots of
NA's and I used knn imputation to fill in other gaps.
2008 Sep 27
1
ariable Importance Measure in Package RandomForest
Hi,
I've a question about the RandomForest package.
The package allows the extraction of a variable importance measure. As far as
I could see from the documentation, the computation is based on the Gini index.
Do you know if this extraction can be also based on other criteria? In particular,
I'm interested in the info gain criterion.
Best regards,
Chris
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