public static boolean testMeansUnknownEqualVars(double xbar, double ybar, int n, int m, double stdx, double stdy, boolean is_twoTailed, double aLevel) {
        if(n<=1 || stdx<=0 || m<=1 || stdy<=0) {
            throw new IllegalArgumentException("The values of the provided parameters are not within the permitted range.");
        }

        double PooledVariance=((n-1)*stdx*stdx+(m-1)*stdy*stdy)/(n+m-2.0);

        //standardize it
        double t=(xbar-ybar)/Math.sqrt(PooledVariance/n+PooledVariance/m);

        int df=n+m-2;

        boolean rejectH0=checkCriticalValue(t, df, is_twoTailed, aLevel);

        return rejectH0;
    }
public static boolean testMeansUnknownEqualVars ( double xbar , double ybar , int n , int m , double stdx , double stdy , boolean is_twoTailed , double aLevel ) { if ( n <= 1 || stdx <= 0 || m <= 1 || stdy <= 0 ) { throw new IllegalArgumentException ( "The values of the provided parameters are not within the permitted range." ) ; } double PooledVariance = ( ( n - 1 ) * stdx * stdx + ( m - 1 ) * stdy * stdy ) / ( n + m - 2.0 ) ; double t = ( xbar - ybar ) / Math . sqrt ( PooledVariance / n + PooledVariance / m ) ; int df = n + m - 2 ; boolean rejectH0 = checkCriticalValue ( t , df , is_twoTailed , aLevel ) ; return rejectH0 ; }
Independent Samples Mean Test for Students.
Requirements: Normal with unknown Variances, equal variances

@param xbar
@param ybar
@param n
@param m
@param stdx
@param stdy
@param is_twoTailed
@param aLevel
@return