question: private int sequentialForwardSelection ( String dataFile , String [ ] features , int indVarColNumber , int X [ ] , int Y [ ] , double J [ ] , int rowIni , int rowEnd ) { double sig [ ] = new double [ Y . length ] ; int sigIndex [ ] = new int [ Y . length ] ; double corXplusy [ ] = new double [ Y . length ] ; double corX ; if ( X . length > 0 ) { Regression reg = new Regression ( ) ; reg . multipleLinearRegression ( dataFile , indVarColNumber , X , features , interceptTerm , rowIni , rowEnd ) ; corX = reg . getCorrelation ( ) ; } else corX = 0.0 ; for ( int i = 0 ; i < Y . length ; i ++ ) { corXplusy [ i ] = correlationOfNewFeature ( dataFile , features , indVarColNumber , X , Y [ i ] , rowIni , rowEnd ) ; sig [ i ] = corXplusy [ i ] - corX ; sigIndex [ i ] = Y [ i ] ; } int minSig = MathUtils . getMinIndex ( sig ) ; J [ 0 ] = corXplusy [ minSig ] ; J [ 1 ] = corX ; int maxSig = MathUtils . getMaxIndex ( sig ) ; J [ 2 ] = corXplusy [ maxSig ] ; return sigIndex [ maxSig ] ; }
target:  Find the f feature in Y that maximise J(X+y)