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diff --git a/src/main/java/org/apache/commons/math3/stat/ranking/TiesStrategy.java b/src/main/java/org/apache/commons/math3/stat/ranking/TiesStrategy.java
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+/*
+ * 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.math3.stat.ranking;
+
+/**
+ * Strategies for handling tied values in rank transformations.
+ * <ul>
+ * <li>SEQUENTIAL - Ties are assigned ranks in order of occurrence in the original array,
+ * for example (1,3,4,3) is ranked as (1,2,4,3)</li>
+ * <li>MINIMUM - Tied values are assigned the minimum applicable rank, or the rank
+ * of the first occurrence. For example, (1,3,4,3) is ranked as (1,2,4,2)</li>
+ * <li>MAXIMUM - Tied values are assigned the maximum applicable rank, or the rank
+ * of the last occurrence. For example, (1,3,4,3) is ranked as (1,3,4,3)</li>
+ * <li>AVERAGE - Tied values are assigned the average of the applicable ranks.
+ * For example, (1,3,4,3) is ranked as (1,2.5,4,2.5)</li>
+ * <li>RANDOM - Tied values are assigned a random integer rank from among the
+ * applicable values. The assigned rank will always be an integer, (inclusively)
+ * between the values returned by the MINIMUM and MAXIMUM strategies.</li>
+ * </ul>
+ *
+ * @since 2.0
+ */
+public enum TiesStrategy {
+
+    /** Ties assigned sequential ranks in order of occurrence */
+    SEQUENTIAL,
+
+    /** Ties get the minimum applicable rank */
+    MINIMUM,
+
+    /** Ties get the maximum applicable rank */
+    MAXIMUM,
+
+    /** Ties get the average of applicable ranks */
+    AVERAGE,
+
+    /** Ties get a random integral value from among applicable ranks */
+    RANDOM
+}