[R] How to fix false positve rates?

Berton Gunter gunter.berton at gene.com
Wed Jun 15 00:22:38 CEST 2005


 

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Anderson de Rezende
Rocha
Sent: Tuesday, June 14, 2005 11:01 AM
To: r-help at stat.math.ethz.ch
Subject: [R] How to fix false positve rates?

Dear R-users, 

I have a set of 12000 image samples. I can divide this set into two
categories: training and testing. I need to classify the test set into
a two qualitative outputs: true or false for some characteristic. 

To do the classification I'm using the packages SVM in e1071 library
and LDA in the MASS library. However, I'm with a great number of FALSE
POSITIVE CASES in both classifiers, about 10/15%. 

1) How can I use these classifiers with a fixed 1% FALSE POSITIVE RATE?

Surely you jest! Classification is not hypothesis testing.You do not get to
control either false positive or negative rates. You try to minimize (an
unbiased estimate of) mislclassification rate.

2) Could anynone indicate me a non-linear SVM classifier R-package?
3) Could anynone indicate me an ADA-BOOST classifier R-package?

Look! 
RSiteSearch('boosting', restrict = 'functions')

Cheers,
Bert Gunter



Thanks for all. I'm anxiously wait the answers. Best regards. 

*************************************************
|Üñðë®§µñ| - Anderson de Rezende Rocha
Bacharel em Ciência da Computação - UFLA
Mestrando em Ciência da Computação - UNICAMP
Esteganografia e esteganálise digital
UNIVERSIDADE ESTADUAL DE CAMPINAS, SP - BRASIL
< http://andersonrocha.cjb.net >

______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html




More information about the R-help mailing list