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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.
+#
+
+# $example on$
+from pyspark.mllib.classification import LogisticRegressionWithLBFGS
+from pyspark.mllib.util import MLUtils
+from pyspark.mllib.evaluation import MulticlassMetrics
+# $example off$
+
+from pyspark import SparkContext
+
+if __name__ == "__main__":
+ sc = SparkContext(appName="MultiClassMetricsExample")
+
+ # Several of the methods available in scala are currently missing from pyspark
+ # $example on$
+ # Load training data in LIBSVM format
+ data = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_multiclass_classification_data.txt")
+
+ # Split data into training (60%) and test (40%)
+ training, test = data.randomSplit([0.6, 0.4], seed=11L)
+ training.cache()
+
+ # Run training algorithm to build the model
+ model = LogisticRegressionWithLBFGS.train(training, numClasses=3)
+
+ # Compute raw scores on the test set
+ predictionAndLabels = test.map(lambda lp: (float(model.predict(lp.features)), lp.label))
+
+ # Instantiate metrics object
+ metrics = MulticlassMetrics(predictionAndLabels)
+
+ # Overall statistics
+ precision = metrics.precision()
+ recall = metrics.recall()
+ f1Score = metrics.fMeasure()
+ print("Summary Stats")
+ print("Precision = %s" % precision)
+ print("Recall = %s" % recall)
+ print("F1 Score = %s" % f1Score)
+
+ # Statistics by class
+ labels = data.map(lambda lp: lp.label).distinct().collect()
+ for label in sorted(labels):
+ print("Class %s precision = %s" % (label, metrics.precision(label)))
+ print("Class %s recall = %s" % (label, metrics.recall(label)))
+ print("Class %s F1 Measure = %s" % (label, metrics.fMeasure(label, beta=1.0)))
+
+ # Weighted stats
+ print("Weighted recall = %s" % metrics.weightedRecall)
+ print("Weighted precision = %s" % metrics.weightedPrecision)
+ print("Weighted F(1) Score = %s" % metrics.weightedFMeasure())
+ print("Weighted F(0.5) Score = %s" % metrics.weightedFMeasure(beta=0.5))
+ print("Weighted false positive rate = %s" % metrics.weightedFalsePositiveRate)
+ # $example off$