org.apache.spark.ml.classification

Class OneVsRest

Object

org.apache.spark.ml.PipelineStage

org.apache.spark.ml.Estimator<OneVsRestModel>

org.apache.spark.ml.classification.OneVsRest

All Implemented Interfaces:

java.io.Serializable, Logging, Params, Identifiable, MLWritable

public final class OneVsRest
extends Estimator<OneVsRestModel>
implements MLWritable

Reduction of Multiclass Classification to Binary Classification. Performs reduction using one against all strategy. For a multiclass classification with k classes, train k models (one per class). Each example is scored against all k models and the model with highest score is picked to label the example.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
OneVsRest()
OneVsRest(String uid)

Method Summary

Modifier and Type	Method and Description
static Param<Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>>	classifier()
Param<Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>>	classifier() param for the base binary classifier that we reduce multiclass classification into.
static Params	clear(Param<?> param)
OneVsRest	copy(ParamMap extra) Creates a copy of this instance with the same UID and some extra params.
static String	explainParam(Param<?> param)
static String	explainParams()
static ParamMap	extractParamMap()
static ParamMap	extractParamMap(ParamMap extra)
static Param<String>	featuresCol()
OneVsRestModel	fit(Dataset<?> dataset) Fits a model to the input data.
static <T> scala.Option<T>	get(Param<T> param)
static Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>	getClassifier()
Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>	getClassifier()
static <T> scala.Option<T>	getDefault(Param<T> param)
static String	getFeaturesCol()
static String	getLabelCol()
static <T> T	getOrDefault(Param<T> param)
static int	getParallelism()
static Param<Object>	getParam(String paramName)
static String	getPredictionCol()
static String	getRawPredictionCol()
static String	getWeightCol()
static <T> boolean	hasDefault(Param<T> param)
static boolean	hasParam(String paramName)
static boolean	isDefined(Param<?> param)
static boolean	isSet(Param<?> param)
static Param<String>	labelCol()
static OneVsRest	load(String path)
static IntParam	parallelism()
static Param<?>[]	params()
static Param<String>	predictionCol()
static Param<String>	rawPredictionCol()
static MLReader<OneVsRest>	read()
static void	save(String path)
static <T> Params	set(Param<T> param, T value)
OneVsRest	setClassifier(Classifier<?,?,?> value)
OneVsRest	setFeaturesCol(String value)
OneVsRest	setLabelCol(String value)
OneVsRest	setParallelism(int value) The implementation of parallel one vs.
OneVsRest	setPredictionCol(String value)
OneVsRest	setRawPredictionCol(String value)
OneVsRest	setWeightCol(String value) Sets the value of param weightCol.
static String	toString()
StructType	transformSchema(StructType schema) :: DeveloperApi ::
String	uid() An immutable unique ID for the object and its derivatives.
StructType	validateAndTransformSchema(StructType schema, boolean fitting, DataType featuresDataType)
static Param<String>	weightCol()
MLWriter	write() Returns an MLWriter instance for this ML instance.

Methods inherited from class org.apache.spark.ml.Estimator

fit, fit, fit, fit

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.spark.ml.param.shared.HasRawPredictionCol

getRawPredictionCol, rawPredictionCol

Methods inherited from interface org.apache.spark.ml.param.Params

clear, copyValues, defaultCopy, defaultParamMap, explainParam, explainParams, extractParamMap, extractParamMap, get, getDefault, getOrDefault, getParam, hasDefault, hasParam, isDefined, isSet, paramMap, params, set, set, set, setDefault, setDefault, shouldOwn

Methods inherited from interface org.apache.spark.ml.util.Identifiable

toString

Methods inherited from interface org.apache.spark.ml.param.shared.HasWeightCol

getWeightCol, weightCol

Methods inherited from interface org.apache.spark.ml.util.MLWritable

save

Methods inherited from interface org.apache.spark.internal.Logging

initializeLogging, initializeLogIfNecessary, initializeLogIfNecessary, isTraceEnabled, log_, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning

Constructor Detail

OneVsRest

public OneVsRest(String uid)

OneVsRest

public OneVsRest()

Method Detail

read

public static MLReader<OneVsRest> read()

load

public static OneVsRest load(String path)

toString

public static String toString()

params

public static Param<?>[] params()

explainParam

public static String explainParam(Param<?> param)

explainParams

public static String explainParams()

isSet

public static final boolean isSet(Param<?> param)

isDefined

public static final boolean isDefined(Param<?> param)

hasParam

public static boolean hasParam(String paramName)

getParam

public static Param<Object> getParam(String paramName)

set

public static final <T> Params set(Param<T> param,
                                   T value)

get

public static final <T> scala.Option<T> get(Param<T> param)

clear

public static final Params clear(Param<?> param)

getOrDefault

public static final <T> T getOrDefault(Param<T> param)

getDefault

public static final <T> scala.Option<T> getDefault(Param<T> param)

hasDefault

public static final <T> boolean hasDefault(Param<T> param)

extractParamMap

public static final ParamMap extractParamMap(ParamMap extra)

extractParamMap

public static final ParamMap extractParamMap()

labelCol

public static final Param<String> labelCol()

getLabelCol

public static final String getLabelCol()

featuresCol

public static final Param<String> featuresCol()

getFeaturesCol

public static final String getFeaturesCol()

predictionCol

public static final Param<String> predictionCol()

getPredictionCol

public static final String getPredictionCol()

rawPredictionCol

public static final Param<String> rawPredictionCol()

getRawPredictionCol

public static final String getRawPredictionCol()

weightCol

public static final Param<String> weightCol()

getWeightCol

public static final String getWeightCol()

classifier

public static Param<Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>> classifier()

getClassifier

public static Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>> getClassifier()

parallelism

public static IntParam parallelism()

getParallelism

public static int getParallelism()

save

public static void save(String path)
                 throws java.io.IOException

Throws:

java.io.IOException

uid

public String uid()

Description copied from interface: Identifiable

An immutable unique ID for the object and its derivatives.

Specified by:

uid in interface Identifiable

Returns:

(undocumented)

setClassifier

public OneVsRest setClassifier(Classifier<?,?,?> value)

setLabelCol

public OneVsRest setLabelCol(String value)

setFeaturesCol

public OneVsRest setFeaturesCol(String value)

setPredictionCol

public OneVsRest setPredictionCol(String value)

setRawPredictionCol

public OneVsRest setRawPredictionCol(String value)

setParallelism

public OneVsRest setParallelism(int value)

The implementation of parallel one vs. rest runs the classification for each class in a separate threads.

Parameters:

value - (undocumented)

Returns:

(undocumented)

setWeightCol

public OneVsRest setWeightCol(String value)

Sets the value of param weightCol.

This is ignored if weight is not supported by classifier. If this is not set or empty, we treat all instance weights as 1.0. Default is not set, so all instances have weight one.

Parameters:

value - (undocumented)

Returns:

(undocumented)

transformSchema

public StructType transformSchema(StructType schema)

Description copied from class: PipelineStage

:: DeveloperApi ::

Check transform validity and derive the output schema from the input schema.

We check validity for interactions between parameters during transformSchema and raise an exception if any parameter value is invalid. Parameter value checks which do not depend on other parameters are handled by Param.validate().

Typical implementation should first conduct verification on schema change and parameter validity, including complex parameter interaction checks.

Specified by:

transformSchema in class PipelineStage

Parameters:

schema - (undocumented)

Returns:

(undocumented)

fit

public OneVsRestModel fit(Dataset<?> dataset)

Description copied from class: Estimator

Fits a model to the input data.

Specified by:

fit in class Estimator<OneVsRestModel>

Parameters:

dataset - (undocumented)

Returns:

(undocumented)

copy

public OneVsRest copy(ParamMap extra)

Description copied from interface: Params

Creates a copy of this instance with the same UID and some extra params. Subclasses should implement this method and set the return type properly. See defaultCopy().

Specified by:

copy in interface Params

Specified by:

copy in class Estimator<OneVsRestModel>

Parameters:

extra - (undocumented)

Returns:

(undocumented)

write

public MLWriter write()

Description copied from interface: MLWritable

Returns an MLWriter instance for this ML instance.

Specified by:

write in interface MLWritable

Returns:

(undocumented)

classifier

public Param<Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>>> classifier()

param for the base binary classifier that we reduce multiclass classification into. The base classifier input and output columns are ignored in favor of the ones specified in OneVsRest.

Returns:

(undocumented)

getClassifier

public Classifier<?,? extends Classifier<Object,Classifier,ClassificationModel>,? extends ClassificationModel<Object,ClassificationModel>> getClassifier()

validateAndTransformSchema

public StructType validateAndTransformSchema(StructType schema,
                                             boolean fitting,
                                             DataType featuresDataType)