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diff --git a/src/main/java/org/apache/commons/math3/stat/interval/ConfidenceInterval.java b/src/main/java/org/apache/commons/math3/stat/interval/ConfidenceInterval.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.interval;
+
+import org.apache.commons.math3.exception.MathIllegalArgumentException;
+import org.apache.commons.math3.exception.util.LocalizedFormats;
+
+/**
+ * Represents an interval estimate of a population parameter.
+ *
+ * @since 3.3
+ */
+public class ConfidenceInterval {
+
+    /** Lower endpoint of the interval */
+    private double lowerBound;
+
+    /** Upper endpoint of the interval */
+    private double upperBound;
+
+    /**
+     * The asserted probability that the interval contains the population
+     * parameter
+     */
+    private double confidenceLevel;
+
+    /**
+     * Create a confidence interval with the given bounds and confidence level.
+     * <p>
+     * Preconditions:
+     * <ul>
+     * <li>{@code lower} must be strictly less than {@code upper}</li>
+     * <li>{@code confidenceLevel} must be strictly between 0 and 1 (exclusive)</li>
+     * </ul>
+     * </p>
+     *
+     * @param lowerBound lower endpoint of the interval
+     * @param upperBound upper endpoint of the interval
+     * @param confidenceLevel coverage probability
+     * @throws MathIllegalArgumentException if the preconditions are not met
+     */
+    public ConfidenceInterval(double lowerBound, double upperBound, double confidenceLevel) {
+        checkParameters(lowerBound, upperBound, confidenceLevel);
+        this.lowerBound = lowerBound;
+        this.upperBound = upperBound;
+        this.confidenceLevel = confidenceLevel;
+    }
+
+    /**
+     * @return the lower endpoint of the interval
+     */
+    public double getLowerBound() {
+        return lowerBound;
+    }
+
+    /**
+     * @return the upper endpoint of the interval
+     */
+    public double getUpperBound() {
+        return upperBound;
+    }
+
+    /**
+     * @return the asserted probability that the interval contains the
+     *         population parameter
+     */
+    public double getConfidenceLevel() {
+        return confidenceLevel;
+    }
+
+    /**
+     * @return String representation of the confidence interval
+     */
+    @Override
+    public String toString() {
+        return "[" + lowerBound + ";" + upperBound + "] (confidence level:" + confidenceLevel + ")";
+    }
+
+    /**
+     * Verifies that (lower, upper) is a valid non-empty interval and confidence
+     * is strictly between 0 and 1.
+     *
+     * @param lower lower endpoint
+     * @param upper upper endpoint
+     * @param confidence confidence level
+     */
+    private void checkParameters(double lower, double upper, double confidence) {
+        if (lower >= upper) {
+            throw new MathIllegalArgumentException(LocalizedFormats.LOWER_BOUND_NOT_BELOW_UPPER_BOUND, lower, upper);
+        }
+        if (confidence <= 0 || confidence >= 1) {
+            throw new MathIllegalArgumentException(LocalizedFormats.OUT_OF_BOUNDS_CONFIDENCE_LEVEL, confidence, 0, 1);
+        }
+    }
+}