diff --git a/samoa-api/src/main/java/org/apache/samoa/evaluation/F1ClassificationPerformanceEvaluator.java b/samoa-api/src/main/java/org/apache/samoa/evaluation/F1ClassificationPerformanceEvaluator.java
new file mode 100644
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--- /dev/null
+++ b/samoa-api/src/main/java/org/apache/samoa/evaluation/F1ClassificationPerformanceEvaluator.java
@@ -0,0 +1,146 @@
+package org.apache.samoa.evaluation;
+
+/*
+ * #%L
+ * SAMOA
+ * %%
+ * Copyright (C) 2014 - 2016 Apache Software Foundation
+ * %%
+ * Licensed 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.
+ * #L%
+ */
+
+
+import org.apache.samoa.instances.Instance;
+import org.apache.samoa.instances.Utils;
+import org.apache.samoa.moa.AbstractMOAObject;
+import org.apache.samoa.moa.core.Measurement;
+
+/**
+ * Created by Edi Bice (edi.bice gmail com) on 2/22/2016.
+ */
+public class F1ClassificationPerformanceEvaluator extends AbstractMOAObject implements
+        ClassificationPerformanceEvaluator {
+
+    private static final long serialVersionUID = 1L;
+    protected int numClasses;
+
+    protected long[] support;
+    protected long[] truePos;
+    protected long[] falsePos;
+    protected long[] trueNeg;
+    protected long[] falseNeg;
+
+    @Override
+    public void reset() {
+        reset(this.numClasses);
+    }
+
+    public void reset(int numClasses) {
+        this.numClasses = numClasses;
+        this.truePos = new long[numClasses];
+        this.falsePos = new long[numClasses];
+        this.trueNeg = new long[numClasses];
+        this.falseNeg = new long[numClasses];
+        for (int i = 0; i < this.numClasses; i++) {
+            this.support[i] = 0;
+            this.truePos[i] = 0;
+            this.falsePos[i] = 0;
+            this.trueNeg[i] = 0;
+            this.falseNeg[i] = 0;
+        }
+    }
+
+    @Override
+    public void addResult(Instance inst, double[] classVotes) {
+        int trueClass = (int) inst.classValue();
+        this.support[trueClass] += 1;
+        int predictedClass = Utils.maxIndex(classVotes);
+        if (predictedClass == trueClass) {
+            this.truePos[trueClass] += 1;
+            for (int i = 0; i < this.numClasses; i++) {
+                if (i!=predictedClass) this.trueNeg[i] += 1;
+            }
+        } else {
+            this.falsePos[predictedClass] += 1;
+            this.falseNeg[trueClass] += 1;
+            for (int i = 0; i < this.numClasses; i++) {
+                if (!(i==predictedClass || i==trueClass)) this.trueNeg[i] += 1;
+            }
+        }
+    }
+
+    @Override
+    public Measurement[] getPerformanceMeasurements() {
+        return getF1Measurements();
+    }
+
+    private Measurement[] getSupportMeasurements() {
+        Measurement[] measurements = new Measurement[this.numClasses];
+        for (int i = 0; i < this.numClasses; i++) {
+            String ml = String.format("class %s support", i);
+            measurements[i] = new Measurement(ml, this.support[i]);
+        }
+        return measurements;
+    }
+
+    private Measurement[] getPrecisionMeasurements() {
+        Measurement[] measurements = new Measurement[this.numClasses];
+        for (int i = 0; i < this.numClasses; i++) {
+            String ml = String.format("class %s precision", i);
+            measurements[i] = new Measurement(ml, getPrecision(i));
+        }
+        return measurements;
+    }
+
+    private Measurement[] getRecallMeasurements() {
+        Measurement[] measurements = new Measurement[this.numClasses];
+        for (int i = 0; i < this.numClasses; i++) {
+            String ml = String.format("class %s recall", i);
+            measurements[i] = new Measurement(ml, getRecall(i));
+        }
+        return measurements;
+    }
+
+    private Measurement[] getF1Measurements() {
+        Measurement[] measurements = new Measurement[this.numClasses];
+        for (int i = 0; i < this.numClasses; i++) {
+            String ml = String.format("class %s f1-score", i);
+            measurements[i] = new Measurement(ml, getF1Score(i));
+        }
+        return measurements;
+    }
+
+    @Override
+    public void getDescription(StringBuilder sb, int indent) {
+        Measurement.getMeasurementsDescription(getSupportMeasurements(), sb, indent);
+        Measurement.getMeasurementsDescription(getPrecisionMeasurements(), sb, indent);
+        Measurement.getMeasurementsDescription(getRecallMeasurements(), sb, indent);
+        Measurement.getMeasurementsDescription(getF1Measurements(), sb, indent);
+    }
+
+    private double getPrecision(int classIndex) {
+        return (double) this.truePos[classIndex] / (this.truePos[classIndex] + this.falsePos[classIndex]);
+    }
+
+    private double getRecall(int classIndex) {
+        return (double) this.truePos[classIndex] / (this.truePos[classIndex] + this.falseNeg[classIndex]);
+    }
+
+    private double getF1Score(int classIndex) {
+        double precision = getPrecision(classIndex);
+        double recall = getRecall(classIndex);
+        return 2 * (precision * recall) / (precision + recall);
+    }
+
+}