org.apache.spark.ml.evaluation

Class Evaluator

Object

org.apache.spark.ml.evaluation.Evaluator

All Implemented Interfaces:

java.io.Serializable, Params

Direct Known Subclasses:

BinaryClassificationEvaluator, RegressionEvaluator

public abstract class Evaluator
extends Object
implements Params

:: DeveloperApi :: Abstract class for evaluators that compute metrics from predictions.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Evaluator()

Method Summary

Methods

Modifier and Type	Method and Description
Evaluator	copy(ParamMap extra) Creates a copy of this instance with the same UID and some extra params.
abstract double	evaluate(DataFrame dataset) Evaluates the output.
double	evaluate(DataFrame dataset, ParamMap paramMap) Evaluates model output and returns a scalar metric (larger is better).

Methods inherited from class Object

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

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

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

Constructor Detail

Evaluator

public Evaluator()

Method Detail

evaluate

public double evaluate(DataFrame dataset,
              ParamMap paramMap)

Evaluates model output and returns a scalar metric (larger is better).

Parameters:

dataset - a dataset that contains labels/observations and predictions.

paramMap - parameter map that specifies the input columns and output metrics

Returns:

metric

evaluate

public abstract double evaluate(DataFrame dataset)

Evaluates the output.

Parameters:

dataset - a dataset that contains labels/observations and predictions.

Returns:

metric

copy

public Evaluator copy(ParamMap extra)

Description copied from interface: Params

Creates a copy of this instance with the same UID and some extra params. The default implementation tries to create a new instance with the same UID. Then it copies the embedded and extra parameters over and returns the new instance. Subclasses should override this method if the default approach is not sufficient.

Specified by:

copy in interface Params

Parameters:

extra - (undocumented)

Returns:

(undocumented)