AdaBoost (Mallet 2 API)

java.lang.Object
- cc.mallet.classify.Classifier
- - cc.mallet.classify.AdaBoost

All Implemented Interfaces:

AlphabetCarrying, java.io.Serializable
```
public class AdaBoost
extends Classifier
```
AdaBoost Robert E. Schapire. "The boosting approach to machine learning: An overview." In MSRI Workshop on Nonlinear Estimation and Classification, 2002. http://www.research.att.com/~schapire/cgi-bin/uncompress-papers/msri.ps

Author:

Andrew McCallum mccallum@cs.umass.edu

See Also:

Serialized Form

Field Summary
- Fields inherited from class cc.mallet.classify.Classifier
  instancePipe

Constructor Summary

Constructors
Constructor Description

AdaBoost(Pipe instancePipe, Classifier[] weakClassifiers, double[] alphas)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Classification`	`classify(Instance inst)`
`Classification`	`classify(Instance inst, int numWeakClassifiersToUse)`	Classify the given instance using only the first `numWeakClassifiersToUse` classifiers trained during boosting
`int`	`getNumWeakClassifiers()`	Get the number of weak classifiers in this ensemble classifier
`AdaBoost`	`getTrimmedClassifier(int numWeakClassifiersToUse)`	Return an AdaBoost classifier that uses only the first `numWeakClassifiersToUse` weak learners.

Methods inherited from class cc.mallet.classify.Classifier
alphabetsMatch, classify, classify, classify, getAccuracy, getAlphabet, getAlphabets, getAverageRank, getF1, getF1, getF1, getFeatureSelection, getInstancePipe, getLabelAlphabet, getPerClassFeatureSelection, getPrecision, getPrecision, getPrecision, getRecall, getRecall, getRecall, print, print

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AdaBoost
```
public AdaBoost(Pipe instancePipe,
                Classifier[] weakClassifiers,
                double[] alphas)
```
- Method Detail
  - getNumWeakClassifiers
```
public int getNumWeakClassifiers()
```
    Get the number of weak classifiers in this ensemble classifier
  - getTrimmedClassifier
```
public AdaBoost getTrimmedClassifier(int numWeakClassifiersToUse)
```
    Return an AdaBoost classifier that uses only the first numWeakClassifiersToUse weak learners.
    The returned classifier's Pipe and weak classifiers are backed by the respective objects of this classifier, so changes to the returned classifier's Pipe and weak classifiers are reflected in this classifier, and vice versa.
  - classify
```
public Classification classify(Instance inst)
```
    Specified by:
    
    classify in class Classifier
  - classify
```
public Classification classify(Instance inst,
                               int numWeakClassifiersToUse)
```
    Classify the given instance using only the first numWeakClassifiersToUse classifiers trained during boosting