featureSelectorInit

 

 

USE:

[BIG,x,Adrem] = featureSelectorInit(X,y,nbx, nby,nf,nb,initsel,cvsets,k,alpha,gama,flag)

 

DESCRIPTION:

This function is almost similar with the function featureSelector (see help for details) with the exception that it takes supplementary argument initsel, which is a vector whose elements are integers indicating a initial selection of features to start with in the feature selection process.

 

EXAMPLES:

CLASSIFICATION

//load the iris data set. There are 3 classes and 50 samples in each

> irisdata

// use as relevance measure both AR and ADC and use (l,r) search with r<>0 by starting with a initial selection of features 2 and 4.

> [BIG,x,Adrem] = featureSelectorInit (X,y,10,3,2,1,[1 2],3,1,0.1,0.9,1)

 

REGRESSION

//generate a 5 features matrix X of random numbers. y is generated in such a way that the importance of features of X in predicting y decreases from the 1st to 3rd while the remaining 2 are completely unimportant. 

> X=randn(200,5)

> y=(2*X(:,1).^2-X(:,3))./X(:,2)

 

// Searches best features using as features relevance measure the ADC and forward selection only, as nb is set to 0, but feature 3 is taken as initial selection

> [BIG,x,Adrem] = featureSelectorInit (X,y,5,5,1,0,[3],3,5,0,1,1)

 

 

COMMENTS:

Created by Laurentiu Adi Tarca. Revised 10.07.2003

This help was created on 12.03.2004