| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.math4.stat.inference; |
| |
| import org.apache.commons.math4.exception.DimensionMismatchException; |
| import org.apache.commons.math4.exception.NoDataException; |
| import org.apache.commons.math4.exception.NullArgumentException; |
| import org.apache.commons.math4.exception.NumberIsTooLargeException; |
| import org.junit.Assert; |
| import org.junit.Test; |
| |
| |
| /** |
| * Test cases for the WilcoxonSignedRangTest class. |
| * |
| */ |
| |
| public class WilcoxonSignedRankTestTest { |
| |
| protected WilcoxonSignedRankTest testStatistic = new WilcoxonSignedRankTest(); |
| |
| @Test |
| public void testWilcoxonSignedRankSimple() { |
| /* Target values computed using R version 2.11.1 |
| * x <- c(1.83, 0.50, 1.62, 2.48, 1.68, 1.88, 1.55, 3.06, 1.30) |
| * y <- c(0.878, 0.647, 0.598, 2.05, 1.06, 1.29, 1.06, 3.14, 1.29) |
| */ |
| final double x[] = {1.83, 0.50, 1.62, 2.48, 1.68, 1.88, 1.55, 3.06, 1.30}; |
| final double y[] = {0.878, 0.647, 0.598, 2.05, 1.06, 1.29, 1.06, 3.14, 1.29}; |
| |
| /* EXACT: |
| * wilcox.test(x, y, alternative = "two.sided", mu = 0, paired = TRUE, exact = TRUE, correct = FALSE) |
| * V = 40, p-value = 0.03906 |
| * |
| * Corresponds to the value obtained in R. |
| */ |
| Assert.assertEquals(40, testStatistic.wilcoxonSignedRank(x, y), 1e-10); |
| Assert.assertEquals(0.03906, testStatistic.wilcoxonSignedRankTest(x, y, true), 1e-5); |
| |
| /* ASYMPTOTIC: |
| * wilcox.test(x, y, alternative = "two.sided", mu = 0, paired = TRUE, exact = FALSE, correct = FALSE) |
| * V = 40, p-value = 0.03815 |
| * |
| * This is not entirely the same due to different corrects, |
| * e.g. http://mlsc.lboro.ac.uk/resources/statistics/wsrt.pdf |
| * and src/library/stats/R/wilcox.test.R in the R source |
| */ |
| Assert.assertEquals(40, testStatistic.wilcoxonSignedRank(x, y), 1e-10); |
| Assert.assertEquals(0.0329693812, testStatistic.wilcoxonSignedRankTest(x, y, false), 1e-10); |
| } |
| |
| @Test |
| public void testWilcoxonSignedRankInputValidation() { |
| /* |
| * Exact only for sample size <= 30 |
| */ |
| final double[] x1 = new double[30]; |
| final double[] x2 = new double[31]; |
| final double[] y1 = new double[30]; |
| final double[] y2 = new double[31]; |
| for (int i = 0; i < 30; ++i) { |
| x1[i] = x2[i] = y1[i] = y2[i] = i; |
| } |
| |
| // Exactly 30 is okay |
| //testStatistic.wilcoxonSignedRankTest(x1, y1, true); |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(x2, y2, true); |
| Assert.fail("More than 30 samples and exact chosen, NumberIsTooLargeException expected"); |
| } catch (NumberIsTooLargeException ex) { |
| // expected |
| } |
| |
| /* Samples must be present, i.e. length > 0 |
| */ |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { }, new double[] { 1.0 }, true); |
| Assert.fail("x does not contain samples (exact), NoDataException expected"); |
| } catch (NoDataException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { }, new double[] { 1.0 }, false); |
| Assert.fail("x does not contain samples (asymptotic), NoDataException expected"); |
| } catch (NoDataException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0 }, new double[] { }, true); |
| Assert.fail("y does not contain samples (exact), NoDataException expected"); |
| } catch (NoDataException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0 }, new double[] { }, false); |
| Assert.fail("y does not contain samples (asymptotic), NoDataException expected"); |
| } catch (NoDataException ex) { |
| // expected |
| } |
| |
| /* Samples not same size, i.e. cannot be paired |
| */ |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0, 2.0 }, new double[] { 3.0 }, true); |
| Assert.fail("x and y not same size (exact), DimensionMismatchException expected"); |
| } catch (DimensionMismatchException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0, 2.0 }, new double[] { 3.0 }, false); |
| Assert.fail("x and y not same size (asymptotic), DimensionMismatchException expected"); |
| } catch (DimensionMismatchException ex) { |
| // expected |
| } |
| |
| /* |
| * x and y is null |
| */ |
| try { |
| testStatistic.wilcoxonSignedRankTest(null, null, true); |
| Assert.fail("x and y is null (exact), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(null, null, false); |
| Assert.fail("x and y is null (asymptotic), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| |
| /* |
| * x or y is null |
| */ |
| try { |
| testStatistic.wilcoxonSignedRankTest(null, new double[] { 1.0 }, true); |
| Assert.fail("x is null (exact), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(null, new double[] { 1.0 }, false); |
| Assert.fail("x is null (asymptotic), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0 }, null, true); |
| Assert.fail("y is null (exact), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| |
| try { |
| testStatistic.wilcoxonSignedRankTest(new double[] { 1.0 }, null, false); |
| Assert.fail("y is null (asymptotic), NullArgumentException expected"); |
| } catch (NullArgumentException ex) { |
| // expected |
| } |
| } |
| } |