@Test public void testMannWhitneyUSimple() { /* Target values computed using R version 2.11.1 * x <- c(19, 22, 16, 29, 24) * y <- c(20, 11, 17, 12) * wilcox.test(x, y, alternative = "two.sided", mu = 0, paired = FALSE, exact = FALSE, correct = FALSE) * W = 17, p-value = 0.08641 */ final double x[] = {19, 22, 16, 29, 24}; final double y[] = {20, 11, 17, 12}; Assert.assertEquals(17, testStatistic.mannWhitneyU(x, y), 1e-10); Assert.assertEquals(0.08641, testStatistic.mannWhitneyUTest(x, y), 1e-5); }
@Test public void testBigDataSet() { double[] d1 = new double[1500]; double[] d2 = new double[1500]; for (int i = 0; i < 1500; i++) { d1[i] = 2 * i; d2[i] = 2 * i + 1; } double result = testStatistic.mannWhitneyUTest(d1, d2); Assert.assertTrue(result > 0.1); }
@Test public void testMannWhitneyUInputValidation() { /* Samples must be present, i.e. length > 0 */ try { testStatistic.mannWhitneyUTest(new double[] {}, new double[] {1.0}); Assert.fail("x does not contain samples (exact), NoDataException expected"); } catch (NoDataException ex) { // expected } try { testStatistic.mannWhitneyUTest(new double[] {1.0}, new double[] {}); Assert.fail("y does not contain samples (exact), NoDataException expected"); } catch (NoDataException ex) { // expected } /* * x and y is null */ try { testStatistic.mannWhitneyUTest(null, null); Assert.fail("x and y is null (exact), NullArgumentException expected"); } catch (NullArgumentException ex) { // expected } try { testStatistic.mannWhitneyUTest(null, null); Assert.fail("x and y is null (asymptotic), NullArgumentException expected"); } catch (NullArgumentException ex) { // expected } /* * x or y is null */ try { testStatistic.mannWhitneyUTest(null, new double[] {1.0}); Assert.fail("x is null (exact), NullArgumentException expected"); } catch (NullArgumentException ex) { // expected } try { testStatistic.mannWhitneyUTest(new double[] {1.0}, null); Assert.fail("y is null (exact), NullArgumentException expected"); } catch (NullArgumentException ex) { // expected } }