Message-ID: <E1I8b78-0004BL-VJ@www19.emo.freenet-rz.de>
Date: 2007-07-11T12:16:14Z
From: strinz at freenet.de
Subject: RWeka control parameters classifiers interface
Hello,
I have some trouble in achieving the desired parametrisation
for the weka classifier functions, using the package RWeka.
The problem is, that the functions
result=classifier(formula, data, subset, na.action, control = Weka_control(mycontrol))
do not seem to be manipulated by the mycontrol- arguments
Perhaps this should be resepected via the handlers- argument ,
but the documentation in this regard is rather sparse.
# ------------- Examples
file =system.file("arff","iris.arff",package="RWeka")
data =read.arff(file=file)
rownames(data)=1:nrow(data)
colnames(data)[ncol(data)] ="class"
library(RWeka)
# Example: no parameter influence
mySMO =make_Weka_classifier(name="weka/classifiers/functions/SMO",class=NULL,handlers=list());
# Using control =Weka_control()
m1 =mySMO(formula=class~.,data=data[,],control=Weka_control(K="weka.classifiers.functions.supportVector.PolyKernel",E=2))
m2 =mySMO(formula=class~.,data=data[,],control=Weka_control(K="weka.classifiers.functions.supportVector.PolyKernel",E=3))
m3 =mySMO(formula=class~.,data=data[,],control=c("K","weka.classifiers.functions.supportVector.PolyKernel","E",3))
# Using predefinded interface, does not work
x1 =SMO(formula=class~.,data=data[,],control=Weka_control(K="weka.classifiers.functions.supportVector.PolyKernel",E=2))
x2 =SMO(formula=class~.,data=data[,],control=Weka_control(K="weka.classifiers.functions.supportVector.PolyKernel",E=3))
m1$call
m2$call
m3$call
x1$call
x2$call
# no differences:
m1
m2
m3
x1
x2
Any suggestions?
Many thanks
Bjoern
many thanks
bjoern