question: private static boolean hasTies ( double [ ] x , double [ ] y ) { final HashSet < Double > values = new HashSet < Double > ( ) ; for ( int i = 0 ; i < x . length ; i ++ ) { if ( ! values . add ( x [ i ] ) ) { return true ; } } for ( int i = 0 ; i < y . length ; i ++ ) { if ( ! values . add ( y [ i ] ) ) { return true ; } } return false ; }
target:  Returns true iff there are ties in the combined sample formed from x and y.