org.apache.ctakes.temporal.ae.feature.selection

Class Chi2FeatureSelection<OUTCOME_T>

java.lang.Object

org.cleartk.ml.feature.transform.TrainableExtractor_ImplBase<OUTCOME_T>

org.apache.ctakes.temporal.ae.feature.selection.FeatureSelection<OUTCOME_T>

org.apache.ctakes.temporal.ae.feature.selection.Chi2FeatureSelection<OUTCOME_T>

All Implemented Interfaces:

com.google.common.base.Predicate<org.cleartk.ml.Feature>, org.cleartk.ml.feature.transform.TrainableExtractor<OUTCOME_T>

public class Chi2FeatureSelection<OUTCOME_T>
extends FeatureSelection<OUTCOME_T>

Selects features via Chi-squared statistics between the features extracted from its sub-extractor and the outcome values they are paired with in classification instances.

Author:

Chen Lin

Field Summary

Fields inherited from class org.apache.ctakes.temporal.ae.feature.selection.FeatureSelection

isTrained, selectedFeatureNames

Fields inherited from class org.cleartk.ml.feature.transform.TrainableExtractor_ImplBase

name

Constructor Summary

Constructors

Constructor and Description
Chi2FeatureSelection(String name)
Chi2FeatureSelection(String name, double threshold)
Chi2FeatureSelection(String name, double threshold, boolean yates) Constructor that can let use control the yate's correction

Method Summary

Modifier and Type	Method and Description
boolean	apply(org.cleartk.ml.Feature feature)
void	load(URI uri)
void	save(URI uri)
void	train(Iterable<org.cleartk.ml.Instance<OUTCOME_T>> instances)

Methods inherited from class org.apache.ctakes.temporal.ae.feature.selection.FeatureSelection

getFeatureName, transform, transform

Methods inherited from class org.cleartk.ml.feature.transform.TrainableExtractor_ImplBase

isTransformable, selectTransformableFeatures

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.google.common.base.Predicate

equals

Constructor Detail

Chi2FeatureSelection

public Chi2FeatureSelection(String name)

Chi2FeatureSelection

public Chi2FeatureSelection(String name,
                            double threshold)

Chi2FeatureSelection

public Chi2FeatureSelection(String name,
                            double threshold,
                            boolean yates)

Constructor that can let use control the yate's correction

Parameters:

name -

threshold -

yates - : true for using yate's correction, false for turn off yate's correction

Method Detail

apply

public boolean apply(org.cleartk.ml.Feature feature)

Specified by:

apply in interface com.google.common.base.Predicate<org.cleartk.ml.Feature>

Overrides:

apply in class FeatureSelection<OUTCOME_T>

train

public void train(Iterable<org.cleartk.ml.Instance<OUTCOME_T>> instances)

save

public void save(URI uri)
          throws IOException

Throws:

IOException

load

public void load(URI uri)
          throws IOException

Throws:

IOException