Displaying 20 results from an estimated 9000 matches similar to: "prune in rpart: choose number terminal nodes"
2012 May 15
2
rpart - predict terminal nodes for new observations
Dear useRs:
Is there a way I could predict the terminal node associated with a new data
entry in an rpart environment? In the example below, if I had a new data
entry with an AM of 5, I would like to link it to the terminal node 2. My
searches led to http://tolstoy.newcastle.edu.au/R/e4/help/08/07/17702.html
but I do not seem to be able to operationalize Professor Ripley's
suggestions.
Many
2012 Sep 04
1
predict rpart newdata - introduce only values variables used in the tree
Dear community,
I've a tree which included at first 23 variables. Then I've pruned this
tree, and there are only 8 variables involved.
I'd like to predict and only introduce in newdata the values of these 8
variables involved. However, as the tree was built with the 23, it asked me
for 15 values, even if it doesn't need them.
Is there a way to introduce only this 8 values?
2001 Jul 02
1
text.rpart: Unwanted NA labels on terminal nodes (PR#1009)
Brian
The following (which is new to rw1030) occurs with both
Windows 98 & Windows ME. I have not tested behaviour
under Unix or Linux, but I expect it is no different.
text.rpart() prints unwanted NAs (presumably in the
splitting criterion position) on terminal nodes.
Criterion <- factor(paste("Leaf", 1:5))
Node <- factor(1:5)
2007 Feb 15
2
Does rpart package have some requirements on the original data set?
Hi,
I am currently studying Decision Trees by using rpart package in R. I
artificially created a data set which includes the dependant variable
(y) and a few independent variables (x1, x2...). The dependant variable
y only comprises 0 and 1. 90% of y are 1 and 10% of y are 0. When I
apply rpart to it, there is no splitting at all.
I am wondering whether this is because of the
2008 Dec 17
1
pruning trees using rpart
Hi,
I am using the packages tree and rpart to build a classification tree to
predict a 0/1 outcome. The package rpart has the advantage that the function
plotcp gives a visual representation of the cross-validation results with a
horizontal line indicating the 1 standard error rule, i.e. the
recommendation to select the most parsimonious model (the smallest tree)
whose error is not more than one
2003 Jul 17
1
Rpart question - labeling nodes with something not in x$frame
I have a tree created with
tr.hh.logcas <- rpart(log(YCASSX + 1)~AGE+DRUGUSEY+SEX+OBSXNUM +WINDLE,
xval = 10)
I would like to label the nodes with YCASSX rather than log(YCASSX +
1). But the help file for text in library rpart says that you can only
use labels that are part of x$frame, which YCASSX is not.
Is there a way to do what I want?
Thanks in advance
Peter
Peter L. Flom, PhD
2009 Nov 30
3
rpart: how to assign observations to nodes in regression trees
Hi,
I am building a regression tree (method=anova) by using rpart package
and as a final result I get the final leaves characterized by
different means and standard deviations for the dependent variable.
However, differently from the classification tree for categorical
variables I cannot find a way to assign each observation to a leaf,
i.e. I can find no frame whcih contains the observation id
2011 Dec 31
1
Cross-validation error with tune and with rpart
Hello list,
I'm trying to generate classifiers for a certain task using several
methods, one of them being decision trees. The doubts come when I want to
estimate the cross-validation error of the generated tree:
tree <- rpart(y~., data=data.frame(xsel, y), cp=0.00001)
ptree <- prune(tree,
cp=tree$cptable[which.min(tree$cptable[,"xerror"]),"CP"])
ptree$cptable
2010 Dec 14
1
rpart - how to estimate the “meaningful” predictors for an outcome (in classification trees)
Hi dear R-help memebers,
When building a CART model (specifically classification tree) using rpart,
it is sometimes obvious that there are variables (X's) that are meaningful
for predicting some of the outcome (y) variables - while other predictors
are relevant for other outcome variables (y's only).
*How can it be estimated, which explanatory variable is "used" for which of
2009 Dec 07
2
problem in labeling the nodes of tree drawn by rpart
Hi all,
I used rpart to fit a model, where the covariates in the model are
categorical variables.
Then I plotted the tree (mytree) and used the command "text" to add labels
to the tree.
In the nodes of the tree, the values of the covariates are represented with
a, b or c.
Is there a way to show the real value(s) of the variable in the nodes
instead of a, b or c ?
I found that the
2008 Mar 06
1
Rpart and bagging - how is it done?
Hi there.
I was wondering if somebody knows how to perform a bagging procedure on a
classification tree without running the classifier with weights.
Let me first explain why I need this and then give some details of what I
have found out so far.
I am thinking about implementing the bagging procedure in Matlab. Matlab
has a simple classification tree function (in their Statistics toolbox) but
2006 Sep 25
2
rpart
Dear r-help-list:
If I use the rpart method like
cfit<-rpart(y~.,data=data,...),
what kind of tree is stored in cfit?
Is it right that this tree is not pruned at all, that it is the full tree?
If so, it's up to me to choose a subtree by using the printcp method.
In the technical report from Atkinson and Therneau "An Introduction to recursive partitioning using the rpart
2012 Aug 01
1
rpart package: why does predict.rpart require values for "unused" predictors?
After fitting and pruning an rpart model, it is often the case that one or
more of the original predictors is not used by any of the splits of the
final tree. It seems logical, therefore, that values for these "unused"
predictors would not be needed for prediction. But when predict() is called
on such models, all predictors seem to be required. Why is that, and can it
be easily
2005 May 04
1
Difference between "tree" and "rpart"
In the help for rpart it says, "This differs from the tree function
mainly in its handling of surrogate variables." And it says that an
rpart object is a superset of a tree object. Both cite Brieman et al.
1984. Both call external code which looks like martian poetry to me.
I've seen posts in the archives where BDR, and other knowledgeable
folks, have said that rpart() is to be
2003 Mar 10
1
rpart returning only 1 node
Hi,
This may actually be a theoretical question.
When I tried to do the following:
##########################################################
> colnames(rating.adclms)
[1] "usage" "mileage" "sex" "excess" "ncd"
[6] "primage" "minage" "drivers" "district" "cargroup"
[11]
2006 Nov 02
1
Question on cross-validation in rpart
Hi R folks,
I am using R version 2.2.1 for Unix. I am exploring the rpart function,
in particular the rpart.control parameter. I have tried using different
values for xval (0, 1, 10, 20) leaving other parameters constant but I
receive the same tree after each run. Is the10 fold cross-validation
default still running every time? I would expect the trees to change at
least a little when I
2018 Aug 14
2
Xenial rpart package on CRAN built with wrong R version?
Hello,
I just upgraded my Ubuntu Xenial system to R 3.5.1 (from 3.4.?) by changing the sources.list entry and doing an "apt-get dist-upgrade". Everything works except loading the rpart package in R:
> library(rpart)
Error: package or namespace load failed for ?rpart?:
package ?rpart? was installed by an R version with different internals; it needs to be reinstalled for use with
2008 Jul 22
2
rpart$where and predict.rpart
Hello there. I have fitted a rpart model.
> rpartModel <- rpart(y~., data=data.frame(y=y,x=x),method="class", ....)
and can use rpart$where to find out the terminal nodes that each
observations belongs.
Now, I have a set of new data and used predict.rpart which seems to give
only the predicted value with no information similar to rpart$where.
May I know how
2009 Jun 09
3
rpart - the xval argument in rpart.control and in xpred.rpart
Dear R users,
I'm working with the rpart package and want to evaluate the performance of
user defined split functions.
I have some problems in understanding the meaning of the xval argument in
the two functions rpart.control and xpred.rpart. In the former it is defined
as the number of cross-validations while in the latter it is defined as the
number of cross-validation groups. If I am
2014 Aug 13
1
Request to review a patch for rpart
Dear list
For my work, it would be helpful if rpart worked seamlessly with an
empty model:
library(rpart); rpart(formula=y~0, data=data.frame(y=factor(1:10)))
Currently, an unrelated error (originating from na.rpart) is thrown.
At some point in the near future, I'd like to release a package to CRAN
which uses rpart and relies on that functionality. I have prepared a
patch (minor