org.apache.spark.ml.evaluation
Class Evaluator

Object
  extended by 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
Evaluator()
           
 
Method Summary
abstract  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, defaultCopy, 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 abstract Evaluator 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.

Specified by:
copy in interface Params
Parameters:
extra - (undocumented)
Returns:
(undocumented)
See Also:
defaultCopy()