Displaying 20 results from an estimated 800 matches similar to: "RWeka and naiveBayes"
2012 Feb 09
1
Tr: Re: how to pass weka classifier options with a meta classifier in RWeka?
Le jeudi 09 f?vrier 2012 ? 15:31 +0200, Kari Ruohonen a ?crit :
> Hi,
> I am trying to replicate a training of AttributeSelectedClassifier with
> CFsSubsetEval, BestFirst and NaiveBayes that I have initially done with
> Weka. Now, I am trying to use RWeka in R.
>
> I have a problem of passing arguments to the CfsSubsetEval, BestFirst
> and NaiveBayes. I have first created an
2010 Aug 28
4
expression() and plot title
What I want to do is put the arguments I supply to a function into the
title of a plot
Say I'm calling func.1
func.1(a=4,b=4)
plot(....,..., title("a=4, b=4"))
If I'm calling func.1 with different arguments, I want the plot title to
reflect that.
A small detail is that func.1 might have an argument with a default like
c=a+b. I tried using expression but couldn't get it to
2008 Oct 16
4
How to save/load RWeka models into/from a file?
Hi,
I want to save a RWeka model into a file, in order to retrive it latter
with a load function.
See this example:
library(RWeka)
NB <- make_Weka_classifier("weka/classifiers/bayes/NaiveBayes")
model<-NB(formula,data=data,...) # does not run but you get the idea
save(model,file="model.dat") # simple save R command
# ...
load("model.dat") # load the model
2012 Nov 12
0
Weka on command line c.f. using RWeka
Running Weka's command line with calls to system(), like this
> system("java weka.classifiers.bayes.NaiveBayes -K -t HWlrTrain.arff -o")
=== Confusion Matrix ===
a b <-- classified as
3518 597 | a = NoSpray
644 926 | b = Spray
=== Stratified cross-validation ===
=== Confusion Matrix ===
a b <-- classified as
3512 603 | a = NoSpray
2012 Feb 07
2
predict.naiveBayes() bug in e1071 package
Hi,
I'm currently using the R package e1071 to train naive bayes
classifiers and came across a bug: When the posterior probabilities of
all classes are small, the result from the predict.naiveBayes function
become NaNs. This is an issue with the treatment of the
log-transformed probabilities inside the predict.naiveBayes function.
Here is an example to demonstrate the problem (you might need
2009 Jun 30
2
NaiveBayes fails with one input variable (caret and klarR packages)
Hello,
We have a system which creates thousands of regression/classification models and in cases where we have only one input variable NaiveBayes throws an error. Maybe I am mistaken and I shouldn't expect to have a model with only one input variable.
We use R version 2.6.0 (2007-10-03). We use caret (v4.1.19), but have tested similar code with klaR (v.0.5.8), because caret relies on
2012 Feb 10
2
naiveBayes: slow predict, weird results
I did this:
nb <- naiveBayes(users, platform)
pl <- predict(nb,users)
nrow(users) ==> 314781
ncol(users) ==> 109
1. naiveBayes() was quite fast (~20 seconds), while predict() was slow
(tens of minutes). why?
2. the predict results were completely off the mark (quite the opposite
of the expected overfitting). suffice it to show the tables:
pl:
android blackberry ipad
2007 Aug 22
1
"subscript out of bounds" Error in predict.naivebayes
I'm trying to fit a naive Bayes model and predict on a new data set using
the functions naivebayes and predict (package = e1071).
R version 2.5.1 on a Linux machine
My data set looks like this. "class" is the response and k1 - k3 are the
independent variables. All of them are factors. The response has 52 levels
and k1 - k3 have 2-6 levels. I have about 9,300 independent variables
2010 Jun 30
1
help on naivebayes function in R
Hi,
I have written a code in R for classifying microarray data using naive
bayes, the code is given below:
library(e1071)
train<-read.table("Z:/Documents/train.txt",header=T);
test<-read.table("Z:/Documents/test.txt",header=T);
cl <- c(c(rep("ALL",10), rep("AML",10)));
cl <- factor(cl)
model <- NaiveBayes(train,cl);
2008 Jun 25
1
Extract naiveBayes details
Hey,
I just like to know how to extract details from the naiveBayes model
(package e1071). I mean, for each possible value the model defines how much
it influences the outcome. I want to sort those probabilities and show the
values with the highest impact.
How could I do that?
PS: I tried using []'s to get to the model's internals, however, all I get
is a "list" not a
2010 Nov 03
2
[klaR package] [NaiveBayes] warning message numerical 0 probability
Hi,
I run R 2.10.1 under ubuntu 10.04 LTS (Lucid Lynx) and klaR version 0.6-4.
I compute a model over a 2 classes dataset (composed of 700 examples).
To that aim, I use the function NaiveBayes provided in the package
klaR.
When I then use the prediction function : predict(my_model, new_data).
I get the following warning :
"In FUN(1:747[[747L]], ...) : Numerical 0 probability with
2012 Nov 08
0
FW: Interfacing R and Weka
-----Original Message-----
From: Patrick Connolly
Sent: Friday, 9 November 2012 11:29 a.m.
To: Peter Alspach
Subject: Interfacing R and Weka
> version
_
platform x86_64-unknown-linux-gnu
arch x86_64
os linux-gnu
system x86_64, linux-gnu
status
major 2
minor 15.2
year 2012
month 10
day 26
svn rev
2006 Mar 03
1
Java related (?) problems with RWeka
Hello all,
I am attempting to run an R script that makes use of RWeka. I am
running SuSE Linux 9.3 with Java 1.5.0_06, R version 2.2.1, Weka
3-4-7, and Rweka 0.2-1.
CLASSPATH="/usr/local/weka-3-4-7/weka.jar:/usr/local/JGR/JGR.jar"
I receive the error:
NewObject("weka/core/Instances","(Ljava/io/Reader;)V",...) failed
Exception in thread "main"
2012 Aug 09
2
Analyzing Poor Performance Using naiveBayes()
My data is 50,000 instances of about 200 predictor values, and for all 50,000
examples I have the actual class labels (binary). The data is quite
unbalanced with about 10% or less of the examples having a positive outcome
and the remainder, of course, negative. Nothing suggests the data has any
order, and it doesn't appear to have any, so I've pulled the first 30,000
examples to use as
2009 Feb 19
1
Bug in predict function for naiveBayes?
Dear all,
I tried a simple naive Bayes classification on an artificial dataset, but I
have troubles getting the predict function to work with the type="class"
specification. With type= "raw", it works perfectly, but with type="class" I
get following error :
Error in as.vector(x, mode) : invalid 'mode' argument
Data : mixture.train is a training set with 100
2007 Jul 11
2
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
2009 Jan 07
1
Question about the RWEKA package
Dear List,
I´m trying to implement the functionalities from WEKA into my modeling project in R through the RWeka package.
In this context I have a slightly special question about the filters implemented in WEKA.
I want to convert nominal attributes with k values into k binary attributes through the NominalToBinary filter ("weka.filters.supervised.attribute.NominalToBinary"). But
2009 Jun 04
1
About classifier in RWeka
Hi everyone,
I have trouble to use RWeka, I tried: (w=weather dataset, all
preditors are nominal)
> m<-J48(play~., data=w)
> e<-evaluate_Weka_classifier(m,cost = matrix(c(0,2,1,0),
+ ncol = 2),numFolds = 10, complexity = TRUE,seed = 123,
+ class = TRUE)
it gives me exactly what I want, but when I tried the same classifier
on the other published data: (iris dataset has all numeric
2009 Dec 01
2
problem with RWeka Weka_control RandomForest
Dear All,
I am finding trouble trying to guild a Wrapper using random forest to
evaluate the subsets:
I do:
nombi <-
make_Weka_filter("weka/filters/supervised/attribute/AttributeSelection")
datbin<- nombi(gene ~., data=X1X2X4X5W, control =Weka_control(
S=list("weka.attributeSelection.GeneticSearch"),
E=list("weka.attributeSelection.WrapperSubsetEval"),B
2007 Aug 01
1
RWeka cross-validation and Weka_control Parametrization
Hello,
I have two questions concerning the RWeka package:
1.) First question:
How can one perform a cross validation, -say 10fold- for a given data set and given model ?
2.) Second question
What is the correct syntax for the parametrization of e.g. Kernel classifiers interface
m1 <- SMO(Species ~ ., data = iris, control =