1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.statistics.inference;
18
19 /**
20 * Contains the result of a test for significance.
21 *
22 * @since 1.1
23 */
24 public interface SignificanceResult {
25 /**
26 * Returns the test statistic.
27 *
28 * @return the statistic
29 */
30 double getStatistic();
31
32 /**
33 * Returns the test statistic p-value.
34 *
35 * <p>The number returned is the smallest significance level at which one can
36 * reject the null hypothesis.
37 *
38 * @return the p-value
39 */
40 double getPValue();
41
42 /**
43 * Returns true iff the null hypothesis can be rejected with {@code 100 * (1 - alpha)}
44 * percent confidence.
45 *
46 * <p>The default implementation uses {@code p < alpha}.
47 *
48 * @param alpha Significance level of the test.
49 * @return true iff null hypothesis can be rejected with confidence {@code 1 - alpha}
50 * @throws IllegalArgumentException if {@code alpha} is not in the range {@code (0, 0.5]}.
51 */
52 default boolean reject(double alpha) {
53 Arguments.checkSignificance(alpha);
54 return getPValue() < alpha;
55 }
56 }