Displaying 20 results from an estimated 10000 matches similar to: "na.action in randomForest"
2003 Aug 05
1
na.action in randomForest --- Summary
A few days ago I asked whether there were options other than
na.action=na.fail for the R port of Breiman?s randomForest; the function?s
help page did not say anything about other options.
I have since discovered that a pdf document called ?The randomForest
Package? and made available by Andy Liaw (who made the tool available in
R---thank you) does discuss an option. It is an implementation of
2003 Aug 26
1
rfImpute (for randomForest) crashed
In trying to execute this line in R (Version 1.7.1 (2003-06-16), under
windows XP pro), with the randomForest library (about two weeks old) loaded,
the program crashed:
bost4rf <- rfImpute(TargetDensity~.,data=bost4rf0)
Specifically, an XP dialog box popped up, saying ?R for windows GUI
front-end has encountered a problem and needs to close.? That was the
dialog saying asking whether I
2003 Apr 02
4
randomForests predict problem
Hello everybody,
I'm testing the randomForest package in order to do some simulations and I
get some trouble with the prediction of new values. The random forest
computation is fine but each time I try to predict values with the newly
created object, I get an error message. I thought I was because NA values
in the dataframe, but I cleaned them and still got the same error. What am
I
2007 Jan 04
3
randomForest and missing data
Does anyone know a reason why, in principle, a call to randomForest
cannot accept a data frame with missing predictor values? If each
individual tree is built using CART, then it seems like this
should be possible. (I understand that one may impute missing values
using rfImpute or some other method, but I would like to avoid doing
that.)
If this functionality were available, then when the trees
2010 Jul 14
1
randomForest outlier return NA
Dear R-users,
I have a problem with randomForest{outlier}.
After running the following code ( that produces a silly data set and builds
a model with randomForest ):
#######################
library(randomForest)
set.seed(0)
## build data set
X <- rbind( matrix( runif(n=400,min=-1,max=1), ncol = 10 ) ,
rep(1,times= 10 ) )
Y <- matrix( nrow = nrow(X), ncol = 1)
for( i in (1:nrow(X))){
2003 Apr 12
5
rpart vs. randomForest
Greetings. I'm trying to determine whether to use rpart or randomForest
for a classification tree. Has anybody tested efficacy formally? I've
run both and the confusion matrix for rf beats rpart. I've looking at
the rf help page and am unable to figure out how to extract the tree.
But more than that I'm looking for a more comprehensive user's guide
for randomForest including
2004 Jan 07
1
Questions on RandomForest
Hi, erveryone,
I show much thanks to Andy and Matthew on former questions. I now sample
only a small segment of a image can segment the image into several classes
by RandomForest successfully. Now I have some confusion on it:
1. What is the internal component classifier in RandomForest? Are they the
CART implemented in the rpart package?
2. I use training samples to predict new samples. But
2004 Dec 10
1
predict.randomForest
I have a data.frame with a series of variables tagged to a binary
response ('present'/'absent'). I am trying to use randomForest to
predict present/absent in a second dataset. After a lot a fiddling
(using two data frames, making sure data types are the same, lots of
testing with data that works such as data(iris)) I've settled on
combining all my data into one data.frame
2003 Aug 15
3
How to reinstall rpart?
After entering ?library(rpart)?, I tried to plot an existing rpart tree, and
got this error message: Error: couldn't find function "plot.rpart".
However, ??plot.rpart? does bring up the help for the function. The same
things occur for text.rpart, although print(my.tree) does work.
So, I tried to re-install rpart using Packages | Install from CRAN, but
then I get this
2003 Mar 14
6
length() misbehaving?
I'm having a weird problem with length(), in R1.6.1 under windows2000. I have a
dataframe called byyr, with ten columns, the first of which is named cnd95.
summary(byyr) shows that byyr$cnd95 contains the factor level "tr" 66 times. Also,
when I enter byyr$cnd95 at the command line, I can count 66 "tr" elements in the
resulting vector. However, when I enter
n95trt <-
2011 Sep 14
1
substitute games with randomForest::partialPlot
I'm having trouble calling randomForest::partialPlot programmatically.
It tries to use name of the (R) variable as the data column name.
Example:
library(randomForest)
iris.rf <- randomForest(Species ~ ., data=iris, importance=TRUE, proximity=TRUE)
partialPlot(iris.rf, iris, Sepal.Width) # works
partialPlot(iris.rf, iris, "Sepal.Width") # works
(function(var.name)
2006 Mar 08
8
how to use the randomForest and rpart function?
Hi all,
I am trying to play around with the randomForest function for
classification. I know its performance is great.
I am currently using the default options.
It has many options.
How do I further tweak the options so that I can make its performance even
better?
What are the options that are mostly used?
Thanks a lot!
M
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2007 Apr 24
1
NA and NaN randomForest
Dear R-help,
This is about randomForest's handling of NA and NaNs in test set data.
Currently, if the test set data contains an NA or NaN then
predict.randomForest will skip that row in the output.
I would like to change that behavior to outputting an NA.
Can this be done with flags to randomForest?
If not can some sort of wrapper be built to put the NAs back in?
thanks,
Clayton
2005 Jan 23
5
How to use "identify"
I can't get identify to work, using R 2.0.1 under windows xp pro,
service pack 2. Here's what I enter, and the result:
> plot((our.frame2$c1),(our.frame2$c9)) # Produces desired plot
> identify(our.frame2$c1) # Plot comes to forefront, so I select a point
warning: no point with 0.25 inches
numeric(0)
Is my call to identify correct? The help page for indentify (from
2005 Jan 20
2
font size in console
I'm using R in a statistics class, and when I project the console, the
font is smaller than ideal. I've checked the faq's, the manual, and the
help system as best I can, and I don't see how to change the font size.
Can it be changed from within a session, or will I have to ask the folks
who installed the program on the server I use in classes to set it
(assuming that can be
2008 Feb 03
2
use classificators learned in R in "real-life", e.g. C
Hi there,
I am interested in using R for machine learning (supervised classification).
Currently, I have been investigating especially the rpart, tree, and randomForest package, and have achieved first results.
are there any experiences, how the learned classificators could
be used in e.g. C ?
in other words, I want to "transfer" the learned predictor from R
to C-code.
for e.g. rpart,
2003 Feb 24
2
trellis.datasets help
I've looked every way I can think of for help on trellis.datasets, but nothing comes
up for me. Please help me find information on what is included, and how to get at
those data. Thanks.
Dave Parkhurst
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.
2011 Feb 10
2
R 2.12.1 Windows 32bit and 64bit - are numerical differences expected?
Should one expect minor numerical differences between 64bit and 32bit R on
Windows? Hunting around the lists I've not been able to find a definitive
answer yet. Seems plausible using different precision arithmetic, but waned
to confirm from those who might know for sure.
BACKGROUND
A colleague was trying to replicate some modelling results (from a soon to
be published book) using rpart, ada,
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