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author | Vikas Nelamangala <vikasnelamangala@Vikass-MacBook-Pro.local> | 2015-11-20 15:18:41 -0800 |
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committer | Xiangrui Meng <meng@databricks.com> | 2015-11-20 15:18:41 -0800 |
commit | ed47b1e660b830e2d4fac8d6df93f634b260393c (patch) | |
tree | 0c3805370f6a088791d7d8767d7ce3e90238b501 /docs | |
parent | 4b84c72dfbb9ddb415fee35f69305b5d7b280891 (diff) | |
download | spark-ed47b1e660b830e2d4fac8d6df93f634b260393c.tar.gz spark-ed47b1e660b830e2d4fac8d6df93f634b260393c.tar.bz2 spark-ed47b1e660b830e2d4fac8d6df93f634b260393c.zip |
[SPARK-11549][DOCS] Replace example code in mllib-evaluation-metrics.md using include_example
Author: Vikas Nelamangala <vikasnelamangala@Vikass-MacBook-Pro.local>
Closes #9689 from vikasnp/master.
Diffstat (limited to 'docs')
-rw-r--r-- | docs/mllib-evaluation-metrics.md | 940 |
1 files changed, 15 insertions, 925 deletions
diff --git a/docs/mllib-evaluation-metrics.md b/docs/mllib-evaluation-metrics.md index f73eff637d..6924037b94 100644 --- a/docs/mllib-evaluation-metrics.md +++ b/docs/mllib-evaluation-metrics.md @@ -104,214 +104,21 @@ data, and evaluate the performance of the algorithm by several binary evaluation <div data-lang="scala" markdown="1"> Refer to the [`LogisticRegressionWithLBFGS` Scala docs](api/scala/index.html#org.apache.spark.mllib.classification.LogisticRegressionWithLBFGS) and [`BinaryClassificationMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.BinaryClassificationMetrics) for details on the API. -{% highlight scala %} -import org.apache.spark.mllib.classification.LogisticRegressionWithLBFGS -import org.apache.spark.mllib.evaluation.BinaryClassificationMetrics -import org.apache.spark.mllib.regression.LabeledPoint -import org.apache.spark.mllib.util.MLUtils - -// Load training data in LIBSVM format -val data = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_binary_classification_data.txt") - -// Split data into training (60%) and test (40%) -val Array(training, test) = data.randomSplit(Array(0.6, 0.4), seed = 11L) -training.cache() - -// Run training algorithm to build the model -val model = new LogisticRegressionWithLBFGS() - .setNumClasses(2) - .run(training) - -// Clear the prediction threshold so the model will return probabilities -model.clearThreshold - -// Compute raw scores on the test set -val predictionAndLabels = test.map { case LabeledPoint(label, features) => - val prediction = model.predict(features) - (prediction, label) -} - -// Instantiate metrics object -val metrics = new BinaryClassificationMetrics(predictionAndLabels) - -// Precision by threshold -val precision = metrics.precisionByThreshold -precision.foreach { case (t, p) => - println(s"Threshold: $t, Precision: $p") -} - -// Recall by threshold -val recall = metrics.recallByThreshold -recall.foreach { case (t, r) => - println(s"Threshold: $t, Recall: $r") -} - -// Precision-Recall Curve -val PRC = metrics.pr - -// F-measure -val f1Score = metrics.fMeasureByThreshold -f1Score.foreach { case (t, f) => - println(s"Threshold: $t, F-score: $f, Beta = 1") -} - -val beta = 0.5 -val fScore = metrics.fMeasureByThreshold(beta) -f1Score.foreach { case (t, f) => - println(s"Threshold: $t, F-score: $f, Beta = 0.5") -} - -// AUPRC -val auPRC = metrics.areaUnderPR -println("Area under precision-recall curve = " + auPRC) - -// Compute thresholds used in ROC and PR curves -val thresholds = precision.map(_._1) - -// ROC Curve -val roc = metrics.roc - -// AUROC -val auROC = metrics.areaUnderROC -println("Area under ROC = " + auROC) - -{% endhighlight %} +{% include_example scala/org/apache/spark/examples/mllib/BinaryClassificationMetricsExample.scala %} </div> <div data-lang="java" markdown="1"> Refer to the [`LogisticRegressionModel` Java docs](api/java/org/apache/spark/mllib/classification/LogisticRegressionModel.html) and [`LogisticRegressionWithLBFGS` Java docs](api/java/org/apache/spark/mllib/classification/LogisticRegressionWithLBFGS.html) for details on the API. -{% highlight java %} -import scala.Tuple2; - -import org.apache.spark.api.java.*; -import org.apache.spark.rdd.RDD; -import org.apache.spark.api.java.function.Function; -import org.apache.spark.mllib.classification.LogisticRegressionModel; -import org.apache.spark.mllib.classification.LogisticRegressionWithLBFGS; -import org.apache.spark.mllib.evaluation.BinaryClassificationMetrics; -import org.apache.spark.mllib.regression.LabeledPoint; -import org.apache.spark.mllib.util.MLUtils; -import org.apache.spark.SparkConf; -import org.apache.spark.SparkContext; - -public class BinaryClassification { - public static void main(String[] args) { - SparkConf conf = new SparkConf().setAppName("Binary Classification Metrics"); - SparkContext sc = new SparkContext(conf); - String path = "data/mllib/sample_binary_classification_data.txt"; - JavaRDD<LabeledPoint> data = MLUtils.loadLibSVMFile(sc, path).toJavaRDD(); - - // Split initial RDD into two... [60% training data, 40% testing data]. - JavaRDD<LabeledPoint>[] splits = data.randomSplit(new double[] {0.6, 0.4}, 11L); - JavaRDD<LabeledPoint> training = splits[0].cache(); - JavaRDD<LabeledPoint> test = splits[1]; - - // Run training algorithm to build the model. - final LogisticRegressionModel model = new LogisticRegressionWithLBFGS() - .setNumClasses(2) - .run(training.rdd()); - - // Clear the prediction threshold so the model will return probabilities - model.clearThreshold(); - - // Compute raw scores on the test set. - JavaRDD<Tuple2<Object, Object>> predictionAndLabels = test.map( - new Function<LabeledPoint, Tuple2<Object, Object>>() { - public Tuple2<Object, Object> call(LabeledPoint p) { - Double prediction = model.predict(p.features()); - return new Tuple2<Object, Object>(prediction, p.label()); - } - } - ); - - // Get evaluation metrics. - BinaryClassificationMetrics metrics = new BinaryClassificationMetrics(predictionAndLabels.rdd()); - - // Precision by threshold - JavaRDD<Tuple2<Object, Object>> precision = metrics.precisionByThreshold().toJavaRDD(); - System.out.println("Precision by threshold: " + precision.toArray()); - - // Recall by threshold - JavaRDD<Tuple2<Object, Object>> recall = metrics.recallByThreshold().toJavaRDD(); - System.out.println("Recall by threshold: " + recall.toArray()); - - // F Score by threshold - JavaRDD<Tuple2<Object, Object>> f1Score = metrics.fMeasureByThreshold().toJavaRDD(); - System.out.println("F1 Score by threshold: " + f1Score.toArray()); - - JavaRDD<Tuple2<Object, Object>> f2Score = metrics.fMeasureByThreshold(2.0).toJavaRDD(); - System.out.println("F2 Score by threshold: " + f2Score.toArray()); - - // Precision-recall curve - JavaRDD<Tuple2<Object, Object>> prc = metrics.pr().toJavaRDD(); - System.out.println("Precision-recall curve: " + prc.toArray()); - - // Thresholds - JavaRDD<Double> thresholds = precision.map( - new Function<Tuple2<Object, Object>, Double>() { - public Double call (Tuple2<Object, Object> t) { - return new Double(t._1().toString()); - } - } - ); - - // ROC Curve - JavaRDD<Tuple2<Object, Object>> roc = metrics.roc().toJavaRDD(); - System.out.println("ROC curve: " + roc.toArray()); - - // AUPRC - System.out.println("Area under precision-recall curve = " + metrics.areaUnderPR()); - - // AUROC - System.out.println("Area under ROC = " + metrics.areaUnderROC()); - - // Save and load model - model.save(sc, "myModelPath"); - LogisticRegressionModel sameModel = LogisticRegressionModel.load(sc, "myModelPath"); - } -} - -{% endhighlight %} +{% include_example java/org/apache/spark/examples/mllib/JavaBinaryClassificationMetricsExample.java %} </div> <div data-lang="python" markdown="1"> Refer to the [`BinaryClassificationMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.BinaryClassificationMetrics) and [`LogisticRegressionWithLBFGS` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.classification.LogisticRegressionWithLBFGS) for more details on the API. -{% highlight python %} -from pyspark.mllib.classification import LogisticRegressionWithLBFGS -from pyspark.mllib.evaluation import BinaryClassificationMetrics -from pyspark.mllib.regression import LabeledPoint -from pyspark.mllib.util import MLUtils - -# Several of the methods available in scala are currently missing from pyspark - -# Load training data in LIBSVM format -data = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_binary_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) - -# Compute raw scores on the test set -predictionAndLabels = test.map(lambda lp: (float(model.predict(lp.features)), lp.label)) - -# Instantiate metrics object -metrics = BinaryClassificationMetrics(predictionAndLabels) - -# Area under precision-recall curve -print("Area under PR = %s" % metrics.areaUnderPR) - -# Area under ROC curve -print("Area under ROC = %s" % metrics.areaUnderROC) - -{% endhighlight %} - +{% include_example python/mllib/binary_classification_metrics_example.py %} </div> </div> @@ -433,204 +240,21 @@ the data, and evaluate the performance of the algorithm by several multiclass cl <div data-lang="scala" markdown="1"> Refer to the [`MulticlassMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.MulticlassMetrics) for details on the API. -{% highlight scala %} -import org.apache.spark.mllib.classification.LogisticRegressionWithLBFGS -import org.apache.spark.mllib.evaluation.MulticlassMetrics -import org.apache.spark.mllib.regression.LabeledPoint -import org.apache.spark.mllib.util.MLUtils - -// Load training data in LIBSVM format -val data = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_multiclass_classification_data.txt") - -// Split data into training (60%) and test (40%) -val Array(training, test) = data.randomSplit(Array(0.6, 0.4), seed = 11L) -training.cache() - -// Run training algorithm to build the model -val model = new LogisticRegressionWithLBFGS() - .setNumClasses(3) - .run(training) - -// Compute raw scores on the test set -val predictionAndLabels = test.map { case LabeledPoint(label, features) => - val prediction = model.predict(features) - (prediction, label) -} - -// Instantiate metrics object -val metrics = new MulticlassMetrics(predictionAndLabels) - -// Confusion matrix -println("Confusion matrix:") -println(metrics.confusionMatrix) - -// Overall Statistics -val precision = metrics.precision -val recall = metrics.recall // same as true positive rate -val f1Score = metrics.fMeasure -println("Summary Statistics") -println(s"Precision = $precision") -println(s"Recall = $recall") -println(s"F1 Score = $f1Score") - -// Precision by label -val labels = metrics.labels -labels.foreach { l => - println(s"Precision($l) = " + metrics.precision(l)) -} - -// Recall by label -labels.foreach { l => - println(s"Recall($l) = " + metrics.recall(l)) -} - -// False positive rate by label -labels.foreach { l => - println(s"FPR($l) = " + metrics.falsePositiveRate(l)) -} - -// F-measure by label -labels.foreach { l => - println(s"F1-Score($l) = " + metrics.fMeasure(l)) -} - -// Weighted stats -println(s"Weighted precision: ${metrics.weightedPrecision}") -println(s"Weighted recall: ${metrics.weightedRecall}") -println(s"Weighted F1 score: ${metrics.weightedFMeasure}") -println(s"Weighted false positive rate: ${metrics.weightedFalsePositiveRate}") - -{% endhighlight %} +{% include_example scala/org/apache/spark/examples/mllib/MulticlassMetricsExample.scala %} </div> <div data-lang="java" markdown="1"> Refer to the [`MulticlassMetrics` Java docs](api/java/org/apache/spark/mllib/evaluation/MulticlassMetrics.html) for details on the API. -{% highlight java %} -import scala.Tuple2; - -import org.apache.spark.api.java.*; -import org.apache.spark.rdd.RDD; -import org.apache.spark.api.java.function.Function; -import org.apache.spark.mllib.classification.LogisticRegressionModel; -import org.apache.spark.mllib.classification.LogisticRegressionWithLBFGS; -import org.apache.spark.mllib.evaluation.MulticlassMetrics; -import org.apache.spark.mllib.regression.LabeledPoint; -import org.apache.spark.mllib.util.MLUtils; -import org.apache.spark.mllib.linalg.Matrix; -import org.apache.spark.SparkConf; -import org.apache.spark.SparkContext; - -public class MulticlassClassification { - public static void main(String[] args) { - SparkConf conf = new SparkConf().setAppName("Multiclass Classification Metrics"); - SparkContext sc = new SparkContext(conf); - String path = "data/mllib/sample_multiclass_classification_data.txt"; - JavaRDD<LabeledPoint> data = MLUtils.loadLibSVMFile(sc, path).toJavaRDD(); - - // Split initial RDD into two... [60% training data, 40% testing data]. - JavaRDD<LabeledPoint>[] splits = data.randomSplit(new double[] {0.6, 0.4}, 11L); - JavaRDD<LabeledPoint> training = splits[0].cache(); - JavaRDD<LabeledPoint> test = splits[1]; - - // Run training algorithm to build the model. - final LogisticRegressionModel model = new LogisticRegressionWithLBFGS() - .setNumClasses(3) - .run(training.rdd()); - - // Compute raw scores on the test set. - JavaRDD<Tuple2<Object, Object>> predictionAndLabels = test.map( - new Function<LabeledPoint, Tuple2<Object, Object>>() { - public Tuple2<Object, Object> call(LabeledPoint p) { - Double prediction = model.predict(p.features()); - return new Tuple2<Object, Object>(prediction, p.label()); - } - } - ); - - // Get evaluation metrics. - MulticlassMetrics metrics = new MulticlassMetrics(predictionAndLabels.rdd()); - - // Confusion matrix - Matrix confusion = metrics.confusionMatrix(); - System.out.println("Confusion matrix: \n" + confusion); - - // Overall statistics - System.out.println("Precision = " + metrics.precision()); - System.out.println("Recall = " + metrics.recall()); - System.out.println("F1 Score = " + metrics.fMeasure()); - - // Stats by labels - for (int i = 0; i < metrics.labels().length; i++) { - System.out.format("Class %f precision = %f\n", metrics.labels()[i], metrics.precision(metrics.labels()[i])); - System.out.format("Class %f recall = %f\n", metrics.labels()[i], metrics.recall(metrics.labels()[i])); - System.out.format("Class %f F1 score = %f\n", metrics.labels()[i], metrics.fMeasure(metrics.labels()[i])); - } - - //Weighted stats - System.out.format("Weighted precision = %f\n", metrics.weightedPrecision()); - System.out.format("Weighted recall = %f\n", metrics.weightedRecall()); - System.out.format("Weighted F1 score = %f\n", metrics.weightedFMeasure()); - System.out.format("Weighted false positive rate = %f\n", metrics.weightedFalsePositiveRate()); - - // Save and load model - model.save(sc, "myModelPath"); - LogisticRegressionModel sameModel = LogisticRegressionModel.load(sc, "myModelPath"); - } -} - -{% endhighlight %} + {% include_example java/org/apache/spark/examples/mllib/JavaMulticlassClassificationMetricsExample.java %} </div> <div data-lang="python" markdown="1"> Refer to the [`MulticlassMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.MulticlassMetrics) for more details on the API. -{% highlight python %} -from pyspark.mllib.classification import LogisticRegressionWithLBFGS -from pyspark.mllib.util import MLUtils -from pyspark.mllib.evaluation import MulticlassMetrics - -# 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) -{% endhighlight %} +{% include_example python/mllib/multi_class_metrics_example.py %} </div> </div> @@ -766,154 +390,21 @@ True classes: <div data-lang="scala" markdown="1"> Refer to the [`MultilabelMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.MultilabelMetrics) for details on the API. -{% highlight scala %} -import org.apache.spark.mllib.evaluation.MultilabelMetrics -import org.apache.spark.rdd.RDD; - -val scoreAndLabels: RDD[(Array[Double], Array[Double])] = sc.parallelize( - Seq((Array(0.0, 1.0), Array(0.0, 2.0)), - (Array(0.0, 2.0), Array(0.0, 1.0)), - (Array(), Array(0.0)), - (Array(2.0), Array(2.0)), - (Array(2.0, 0.0), Array(2.0, 0.0)), - (Array(0.0, 1.0, 2.0), Array(0.0, 1.0)), - (Array(1.0), Array(1.0, 2.0))), 2) - -// Instantiate metrics object -val metrics = new MultilabelMetrics(scoreAndLabels) - -// Summary stats -println(s"Recall = ${metrics.recall}") -println(s"Precision = ${metrics.precision}") -println(s"F1 measure = ${metrics.f1Measure}") -println(s"Accuracy = ${metrics.accuracy}") - -// Individual label stats -metrics.labels.foreach(label => println(s"Class $label precision = ${metrics.precision(label)}")) -metrics.labels.foreach(label => println(s"Class $label recall = ${metrics.recall(label)}")) -metrics.labels.foreach(label => println(s"Class $label F1-score = ${metrics.f1Measure(label)}")) - -// Micro stats -println(s"Micro recall = ${metrics.microRecall}") -println(s"Micro precision = ${metrics.microPrecision}") -println(s"Micro F1 measure = ${metrics.microF1Measure}") - -// Hamming loss -println(s"Hamming loss = ${metrics.hammingLoss}") - -// Subset accuracy -println(s"Subset accuracy = ${metrics.subsetAccuracy}") - -{% endhighlight %} +{% include_example scala/org/apache/spark/examples/mllib/MultiLabelMetricsExample.scala %} </div> <div data-lang="java" markdown="1"> Refer to the [`MultilabelMetrics` Java docs](api/java/org/apache/spark/mllib/evaluation/MultilabelMetrics.html) for details on the API. -{% highlight java %} -import scala.Tuple2; - -import org.apache.spark.api.java.*; -import org.apache.spark.rdd.RDD; -import org.apache.spark.mllib.evaluation.MultilabelMetrics; -import org.apache.spark.SparkConf; -import java.util.Arrays; -import java.util.List; - -public class MultilabelClassification { - public static void main(String[] args) { - SparkConf conf = new SparkConf().setAppName("Multilabel Classification Metrics"); - JavaSparkContext sc = new JavaSparkContext(conf); - - List<Tuple2<double[], double[]>> data = Arrays.asList( - new Tuple2<double[], double[]>(new double[]{0.0, 1.0}, new double[]{0.0, 2.0}), - new Tuple2<double[], double[]>(new double[]{0.0, 2.0}, new double[]{0.0, 1.0}), - new Tuple2<double[], double[]>(new double[]{}, new double[]{0.0}), - new Tuple2<double[], double[]>(new double[]{2.0}, new double[]{2.0}), - new Tuple2<double[], double[]>(new double[]{2.0, 0.0}, new double[]{2.0, 0.0}), - new Tuple2<double[], double[]>(new double[]{0.0, 1.0, 2.0}, new double[]{0.0, 1.0}), - new Tuple2<double[], double[]>(new double[]{1.0}, new double[]{1.0, 2.0}) - ); - JavaRDD<Tuple2<double[], double[]>> scoreAndLabels = sc.parallelize(data); - - // Instantiate metrics object - MultilabelMetrics metrics = new MultilabelMetrics(scoreAndLabels.rdd()); - - // Summary stats - System.out.format("Recall = %f\n", metrics.recall()); - System.out.format("Precision = %f\n", metrics.precision()); - System.out.format("F1 measure = %f\n", metrics.f1Measure()); - System.out.format("Accuracy = %f\n", metrics.accuracy()); - - // Stats by labels - for (int i = 0; i < metrics.labels().length - 1; i++) { - System.out.format("Class %1.1f precision = %f\n", metrics.labels()[i], metrics.precision(metrics.labels()[i])); - System.out.format("Class %1.1f recall = %f\n", metrics.labels()[i], metrics.recall(metrics.labels()[i])); - System.out.format("Class %1.1f F1 score = %f\n", metrics.labels()[i], metrics.f1Measure(metrics.labels()[i])); - } - - // Micro stats - System.out.format("Micro recall = %f\n", metrics.microRecall()); - System.out.format("Micro precision = %f\n", metrics.microPrecision()); - System.out.format("Micro F1 measure = %f\n", metrics.microF1Measure()); - - // Hamming loss - System.out.format("Hamming loss = %f\n", metrics.hammingLoss()); - - // Subset accuracy - System.out.format("Subset accuracy = %f\n", metrics.subsetAccuracy()); - - } -} - -{% endhighlight %} +{% include_example java/org/apache/spark/examples/mllib/JavaMultiLabelClassificationMetricsExample.java %} </div> <div data-lang="python" markdown="1"> Refer to the [`MultilabelMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.MultilabelMetrics) for more details on the API. -{% highlight python %} -from pyspark.mllib.evaluation import MultilabelMetrics - -scoreAndLabels = sc.parallelize([ - ([0.0, 1.0], [0.0, 2.0]), - ([0.0, 2.0], [0.0, 1.0]), - ([], [0.0]), - ([2.0], [2.0]), - ([2.0, 0.0], [2.0, 0.0]), - ([0.0, 1.0, 2.0], [0.0, 1.0]), - ([1.0], [1.0, 2.0])]) - -# Instantiate metrics object -metrics = MultilabelMetrics(scoreAndLabels) - -# Summary stats -print("Recall = %s" % metrics.recall()) -print("Precision = %s" % metrics.precision()) -print("F1 measure = %s" % metrics.f1Measure()) -print("Accuracy = %s" % metrics.accuracy) - -# Individual label stats -labels = scoreAndLabels.flatMap(lambda x: x[1]).distinct().collect() -for label in 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.f1Measure(label))) - -# Micro stats -print("Micro precision = %s" % metrics.microPrecision) -print("Micro recall = %s" % metrics.microRecall) -print("Micro F1 measure = %s" % metrics.microF1Measure) - -# Hamming loss -print("Hamming loss = %s" % metrics.hammingLoss) - -# Subset accuracy -print("Subset accuracy = %s" % metrics.subsetAccuracy) - -{% endhighlight %} +{% include_example python/mllib/multi_label_metrics_example.py %} </div> </div> @@ -1027,280 +518,21 @@ expanded world of non-positive weights are "the same as never having interacted <div data-lang="scala" markdown="1"> Refer to the [`RegressionMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.RegressionMetrics) and [`RankingMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.RankingMetrics) for details on the API. -{% highlight scala %} -import org.apache.spark.mllib.evaluation.{RegressionMetrics, RankingMetrics} -import org.apache.spark.mllib.recommendation.{ALS, Rating} - -// Read in the ratings data -val ratings = sc.textFile("data/mllib/sample_movielens_data.txt").map { line => - val fields = line.split("::") - Rating(fields(0).toInt, fields(1).toInt, fields(2).toDouble - 2.5) -}.cache() - -// Map ratings to 1 or 0, 1 indicating a movie that should be recommended -val binarizedRatings = ratings.map(r => Rating(r.user, r.product, if (r.rating > 0) 1.0 else 0.0)).cache() - -// Summarize ratings -val numRatings = ratings.count() -val numUsers = ratings.map(_.user).distinct().count() -val numMovies = ratings.map(_.product).distinct().count() -println(s"Got $numRatings ratings from $numUsers users on $numMovies movies.") - -// Build the model -val numIterations = 10 -val rank = 10 -val lambda = 0.01 -val model = ALS.train(ratings, rank, numIterations, lambda) - -// Define a function to scale ratings from 0 to 1 -def scaledRating(r: Rating): Rating = { - val scaledRating = math.max(math.min(r.rating, 1.0), 0.0) - Rating(r.user, r.product, scaledRating) -} - -// Get sorted top ten predictions for each user and then scale from [0, 1] -val userRecommended = model.recommendProductsForUsers(10).map{ case (user, recs) => - (user, recs.map(scaledRating)) -} - -// Assume that any movie a user rated 3 or higher (which maps to a 1) is a relevant document -// Compare with top ten most relevant documents -val userMovies = binarizedRatings.groupBy(_.user) -val relevantDocuments = userMovies.join(userRecommended).map{ case (user, (actual, predictions)) => - (predictions.map(_.product), actual.filter(_.rating > 0.0).map(_.product).toArray) -} - -// Instantiate metrics object -val metrics = new RankingMetrics(relevantDocuments) - -// Precision at K -Array(1, 3, 5).foreach{ k => - println(s"Precision at $k = ${metrics.precisionAt(k)}") -} - -// Mean average precision -println(s"Mean average precision = ${metrics.meanAveragePrecision}") - -// Normalized discounted cumulative gain -Array(1, 3, 5).foreach{ k => - println(s"NDCG at $k = ${metrics.ndcgAt(k)}") -} - -// Get predictions for each data point -val allPredictions = model.predict(ratings.map(r => (r.user, r.product))).map(r => ((r.user, r.product), r.rating)) -val allRatings = ratings.map(r => ((r.user, r.product), r.rating)) -val predictionsAndLabels = allPredictions.join(allRatings).map{ case ((user, product), (predicted, actual)) => - (predicted, actual) -} - -// Get the RMSE using regression metrics -val regressionMetrics = new RegressionMetrics(predictionsAndLabels) -println(s"RMSE = ${regressionMetrics.rootMeanSquaredError}") - -// R-squared -println(s"R-squared = ${regressionMetrics.r2}") - -{% endhighlight %} +{% include_example scala/org/apache/spark/examples/mllib/RankingMetricsExample.scala %} </div> <div data-lang="java" markdown="1"> Refer to the [`RegressionMetrics` Java docs](api/java/org/apache/spark/mllib/evaluation/RegressionMetrics.html) and [`RankingMetrics` Java docs](api/java/org/apache/spark/mllib/evaluation/RankingMetrics.html) for details on the API. -{% highlight java %} -import scala.Tuple2; - -import org.apache.spark.api.java.*; -import org.apache.spark.rdd.RDD; -import org.apache.spark.mllib.recommendation.MatrixFactorizationModel; -import org.apache.spark.SparkConf; -import org.apache.spark.api.java.function.Function; -import java.util.*; -import org.apache.spark.mllib.evaluation.RegressionMetrics; -import org.apache.spark.mllib.evaluation.RankingMetrics; -import org.apache.spark.mllib.recommendation.ALS; -import org.apache.spark.mllib.recommendation.Rating; - -// Read in the ratings data -public class Ranking { - public static void main(String[] args) { - SparkConf conf = new SparkConf().setAppName("Ranking Metrics"); - JavaSparkContext sc = new JavaSparkContext(conf); - String path = "data/mllib/sample_movielens_data.txt"; - JavaRDD<String> data = sc.textFile(path); - JavaRDD<Rating> ratings = data.map( - new Function<String, Rating>() { - public Rating call(String line) { - String[] parts = line.split("::"); - return new Rating(Integer.parseInt(parts[0]), Integer.parseInt(parts[1]), Double.parseDouble(parts[2]) - 2.5); - } - } - ); - ratings.cache(); - - // Train an ALS model - final MatrixFactorizationModel model = ALS.train(JavaRDD.toRDD(ratings), 10, 10, 0.01); - - // Get top 10 recommendations for every user and scale ratings from 0 to 1 - JavaRDD<Tuple2<Object, Rating[]>> userRecs = model.recommendProductsForUsers(10).toJavaRDD(); - JavaRDD<Tuple2<Object, Rating[]>> userRecsScaled = userRecs.map( - new Function<Tuple2<Object, Rating[]>, Tuple2<Object, Rating[]>>() { - public Tuple2<Object, Rating[]> call(Tuple2<Object, Rating[]> t) { - Rating[] scaledRatings = new Rating[t._2().length]; - for (int i = 0; i < scaledRatings.length; i++) { - double newRating = Math.max(Math.min(t._2()[i].rating(), 1.0), 0.0); - scaledRatings[i] = new Rating(t._2()[i].user(), t._2()[i].product(), newRating); - } - return new Tuple2<Object, Rating[]>(t._1(), scaledRatings); - } - } - ); - JavaPairRDD<Object, Rating[]> userRecommended = JavaPairRDD.fromJavaRDD(userRecsScaled); - - // Map ratings to 1 or 0, 1 indicating a movie that should be recommended - JavaRDD<Rating> binarizedRatings = ratings.map( - new Function<Rating, Rating>() { - public Rating call(Rating r) { - double binaryRating; - if (r.rating() > 0.0) { - binaryRating = 1.0; - } - else { - binaryRating = 0.0; - } - return new Rating(r.user(), r.product(), binaryRating); - } - } - ); - - // Group ratings by common user - JavaPairRDD<Object, Iterable<Rating>> userMovies = binarizedRatings.groupBy( - new Function<Rating, Object>() { - public Object call(Rating r) { - return r.user(); - } - } - ); - - // Get true relevant documents from all user ratings - JavaPairRDD<Object, List<Integer>> userMoviesList = userMovies.mapValues( - new Function<Iterable<Rating>, List<Integer>>() { - public List<Integer> call(Iterable<Rating> docs) { - List<Integer> products = new ArrayList<Integer>(); - for (Rating r : docs) { - if (r.rating() > 0.0) { - products.add(r.product()); - } - } - return products; - } - } - ); - - // Extract the product id from each recommendation - JavaPairRDD<Object, List<Integer>> userRecommendedList = userRecommended.mapValues( - new Function<Rating[], List<Integer>>() { - public List<Integer> call(Rating[] docs) { - List<Integer> products = new ArrayList<Integer>(); - for (Rating r : docs) { - products.add(r.product()); - } - return products; - } - } - ); - JavaRDD<Tuple2<List<Integer>, List<Integer>>> relevantDocs = userMoviesList.join(userRecommendedList).values(); - - // Instantiate the metrics object - RankingMetrics metrics = RankingMetrics.of(relevantDocs); - - // Precision and NDCG at k - Integer[] kVector = {1, 3, 5}; - for (Integer k : kVector) { - System.out.format("Precision at %d = %f\n", k, metrics.precisionAt(k)); - System.out.format("NDCG at %d = %f\n", k, metrics.ndcgAt(k)); - } - - // Mean average precision - System.out.format("Mean average precision = %f\n", metrics.meanAveragePrecision()); - - // Evaluate the model using numerical ratings and regression metrics - JavaRDD<Tuple2<Object, Object>> userProducts = ratings.map( - new Function<Rating, Tuple2<Object, Object>>() { - public Tuple2<Object, Object> call(Rating r) { - return new Tuple2<Object, Object>(r.user(), r.product()); - } - } - ); - JavaPairRDD<Tuple2<Integer, Integer>, Object> predictions = JavaPairRDD.fromJavaRDD( - model.predict(JavaRDD.toRDD(userProducts)).toJavaRDD().map( - new Function<Rating, Tuple2<Tuple2<Integer, Integer>, Object>>() { - public Tuple2<Tuple2<Integer, Integer>, Object> call(Rating r){ - return new Tuple2<Tuple2<Integer, Integer>, Object>( - new Tuple2<Integer, Integer>(r.user(), r.product()), r.rating()); - } - } - )); - JavaRDD<Tuple2<Object, Object>> ratesAndPreds = - JavaPairRDD.fromJavaRDD(ratings.map( - new Function<Rating, Tuple2<Tuple2<Integer, Integer>, Object>>() { - public Tuple2<Tuple2<Integer, Integer>, Object> call(Rating r){ - return new Tuple2<Tuple2<Integer, Integer>, Object>( - new Tuple2<Integer, Integer>(r.user(), r.product()), r.rating()); - } - } - )).join(predictions).values(); - - // Create regression metrics object - RegressionMetrics regressionMetrics = new RegressionMetrics(ratesAndPreds.rdd()); - - // Root mean squared error - System.out.format("RMSE = %f\n", regressionMetrics.rootMeanSquaredError()); - - // R-squared - System.out.format("R-squared = %f\n", regressionMetrics.r2()); - } -} - -{% endhighlight %} +{% include_example java/org/apache/spark/examples/mllib/JavaRankingMetricsExample.java %} </div> <div data-lang="python" markdown="1"> Refer to the [`RegressionMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.RegressionMetrics) and [`RankingMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.RankingMetrics) for more details on the API. -{% highlight python %} -from pyspark.mllib.recommendation import ALS, Rating -from pyspark.mllib.evaluation import RegressionMetrics, RankingMetrics - -# Read in the ratings data -lines = sc.textFile("data/mllib/sample_movielens_data.txt") - -def parseLine(line): - fields = line.split("::") - return Rating(int(fields[0]), int(fields[1]), float(fields[2]) - 2.5) -ratings = lines.map(lambda r: parseLine(r)) - -# Train a model on to predict user-product ratings -model = ALS.train(ratings, 10, 10, 0.01) - -# Get predicted ratings on all existing user-product pairs -testData = ratings.map(lambda p: (p.user, p.product)) -predictions = model.predictAll(testData).map(lambda r: ((r.user, r.product), r.rating)) - -ratingsTuple = ratings.map(lambda r: ((r.user, r.product), r.rating)) -scoreAndLabels = predictions.join(ratingsTuple).map(lambda tup: tup[1]) - -# Instantiate regression metrics to compare predicted and actual ratings -metrics = RegressionMetrics(scoreAndLabels) - -# Root mean sqaured error -print("RMSE = %s" % metrics.rootMeanSquaredError) - -# R-squared -print("R-squared = %s" % metrics.r2) - -{% endhighlight %} +{% include_example python/mllib/ranking_metrics_example.py %} </div> </div> @@ -1350,163 +582,21 @@ and evaluate the performance of the algorithm by several regression metrics. <div data-lang="scala" markdown="1"> Refer to the [`RegressionMetrics` Scala docs](api/scala/index.html#org.apache.spark.mllib.evaluation.RegressionMetrics) for details on the API. -{% highlight scala %} -import org.apache.spark.mllib.regression.LabeledPoint -import org.apache.spark.mllib.regression.LinearRegressionModel -import org.apache.spark.mllib.regression.LinearRegressionWithSGD -import org.apache.spark.mllib.linalg.Vectors -import org.apache.spark.mllib.evaluation.RegressionMetrics -import org.apache.spark.mllib.util.MLUtils - -// Load the data -val data = MLUtils.loadLibSVMFile(sc, "data/mllib/sample_linear_regression_data.txt").cache() - -// Build the model -val numIterations = 100 -val model = LinearRegressionWithSGD.train(data, numIterations) - -// Get predictions -val valuesAndPreds = data.map{ point => - val prediction = model.predict(point.features) - (prediction, point.label) -} - -// Instantiate metrics object -val metrics = new RegressionMetrics(valuesAndPreds) - -// Squared error -println(s"MSE = ${metrics.meanSquaredError}") -println(s"RMSE = ${metrics.rootMeanSquaredError}") - -// R-squared -println(s"R-squared = ${metrics.r2}") - -// Mean absolute error -println(s"MAE = ${metrics.meanAbsoluteError}") - -// Explained variance -println(s"Explained variance = ${metrics.explainedVariance}") - -{% endhighlight %} +{% include_example scala/org/apache/spark/examples/mllib/RegressionMetricsExample.scala %} </div> <div data-lang="java" markdown="1"> Refer to the [`RegressionMetrics` Java docs](api/java/org/apache/spark/mllib/evaluation/RegressionMetrics.html) for details on the API. -{% highlight java %} -import scala.Tuple2; - -import org.apache.spark.api.java.*; -import org.apache.spark.api.java.function.Function; -import org.apache.spark.mllib.linalg.Vectors; -import org.apache.spark.mllib.regression.LabeledPoint; -import org.apache.spark.mllib.regression.LinearRegressionModel; -import org.apache.spark.mllib.regression.LinearRegressionWithSGD; -import org.apache.spark.mllib.evaluation.RegressionMetrics; -import org.apache.spark.SparkConf; - -public class LinearRegression { - public static void main(String[] args) { - SparkConf conf = new SparkConf().setAppName("Linear Regression Example"); - JavaSparkContext sc = new JavaSparkContext(conf); - - // Load and parse the data - String path = "data/mllib/sample_linear_regression_data.txt"; - JavaRDD<String> data = sc.textFile(path); - JavaRDD<LabeledPoint> parsedData = data.map( - new Function<String, LabeledPoint>() { - public LabeledPoint call(String line) { - String[] parts = line.split(" "); - double[] v = new double[parts.length - 1]; - for (int i = 1; i < parts.length - 1; i++) - v[i - 1] = Double.parseDouble(parts[i].split(":")[1]); - return new LabeledPoint(Double.parseDouble(parts[0]), Vectors.dense(v)); - } - } - ); - parsedData.cache(); - - // Building the model - int numIterations = 100; - final LinearRegressionModel model = - LinearRegressionWithSGD.train(JavaRDD.toRDD(parsedData), numIterations); - - // Evaluate model on training examples and compute training error - JavaRDD<Tuple2<Object, Object>> valuesAndPreds = parsedData.map( - new Function<LabeledPoint, Tuple2<Object, Object>>() { - public Tuple2<Object, Object> call(LabeledPoint point) { - double prediction = model.predict(point.features()); - return new Tuple2<Object, Object>(prediction, point.label()); - } - } - ); - - // Instantiate metrics object - RegressionMetrics metrics = new RegressionMetrics(valuesAndPreds.rdd()); - - // Squared error - System.out.format("MSE = %f\n", metrics.meanSquaredError()); - System.out.format("RMSE = %f\n", metrics.rootMeanSquaredError()); - - // R-squared - System.out.format("R Squared = %f\n", metrics.r2()); - - // Mean absolute error - System.out.format("MAE = %f\n", metrics.meanAbsoluteError()); - - // Explained variance - System.out.format("Explained Variance = %f\n", metrics.explainedVariance()); - - // Save and load model - model.save(sc.sc(), "myModelPath"); - LinearRegressionModel sameModel = LinearRegressionModel.load(sc.sc(), "myModelPath"); - } -} - -{% endhighlight %} +{% include_example java/org/apache/spark/examples/mllib/JavaRegressionMetricsExample.java %} </div> <div data-lang="python" markdown="1"> Refer to the [`RegressionMetrics` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.evaluation.RegressionMetrics) for more details on the API. -{% highlight python %} -from pyspark.mllib.regression import LabeledPoint, LinearRegressionWithSGD -from pyspark.mllib.evaluation import RegressionMetrics -from pyspark.mllib.linalg import DenseVector - -# Load and parse the data -def parsePoint(line): - values = line.split() - return LabeledPoint(float(values[0]), DenseVector([float(x.split(':')[1]) for x in values[1:]])) - -data = sc.textFile("data/mllib/sample_linear_regression_data.txt") -parsedData = data.map(parsePoint) - -# Build the model -model = LinearRegressionWithSGD.train(parsedData) - -# Get predictions -valuesAndPreds = parsedData.map(lambda p: (float(model.predict(p.features)), p.label)) - -# Instantiate metrics object -metrics = RegressionMetrics(valuesAndPreds) - -# Squared Error -print("MSE = %s" % metrics.meanSquaredError) -print("RMSE = %s" % metrics.rootMeanSquaredError) - -# R-squared -print("R-squared = %s" % metrics.r2) - -# Mean absolute error -print("MAE = %s" % metrics.meanAbsoluteError) - -# Explained variance -print("Explained variance = %s" % metrics.explainedVariance) - -{% endhighlight %} +{% include_example python/mllib/regression_metrics_example.py %} </div> </div> |