cc.mallet.fst.semi_supervised
Class CRFTrainerByGE

java.lang.Object
  cc.mallet.fst.TransducerTrainer
      cc.mallet.fst.semi_supervised.CRFTrainerByGE

public class CRFTrainerByGE
extends TransducerTrainer

Trains a CRF using Generalized Expectation constraints that consider either a single label or a pair of labels of a linear chain CRF. See: "Generalized Expectation Criteria for Semi-Supervised Learning of Conditional Random Fields" Gideon Mann and Andrew McCallum ACL 2008

Author:

Gregory Druck

Nested Class Summary

Nested classes/interfaces inherited from class cc.mallet.fst.TransducerTrainer

TransducerTrainer.ByIncrements, TransducerTrainer.ByInstanceIncrements, TransducerTrainer.ByOptimization

Constructor Summary

CRFTrainerByGE(CRF crf, java.util.ArrayList<GEConstraint> constraints)

CRFTrainerByGE(CRF crf, java.util.ArrayList<GEConstraint> constraints, int numThreads)

Method Summary

int	getIteration()
Optimizable.ByGradientValue	getOptimizable(InstanceList unlabeled)
Optimizer	getOptimizer(Optimizable.ByGradientValue optimizable)
Transducer	getTransducer()
boolean	isFinishedTraining()
void	setGaussianPriorVariance(double gpv)
void	setNumResets(int numResets) Sets number of resets of L-BFGS during optimization.
void	setOptimizable(Optimizer optimizer)
void	setStateLabelMap(StateLabelMap map)
boolean	train(InstanceList unlabeledSet, int numIterations) Train the transducer associated with this TransducerTrainer.

Methods inherited from class cc.mallet.fst.TransducerTrainer

addEvaluator, addEvaluators, removeEvaluator, runEvaluators, train

Methods inherited from class java.lang.Object

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

Constructor Detail

CRFTrainerByGE

public CRFTrainerByGE(CRF crf,
                      java.util.ArrayList<GEConstraint> constraints)

CRFTrainerByGE

public CRFTrainerByGE(CRF crf,
                      java.util.ArrayList<GEConstraint> constraints,
                      int numThreads)

Method Detail

getIteration

public int getIteration()

Specified by:

getIteration in class TransducerTrainer

getTransducer

public Transducer getTransducer()

Specified by:

getTransducer in class TransducerTrainer

isFinishedTraining

public boolean isFinishedTraining()

Specified by:

isFinishedTraining in class TransducerTrainer

setGaussianPriorVariance

public void setGaussianPriorVariance(double gpv)

setNumResets

public void setNumResets(int numResets)

Sets number of resets of L-BFGS during optimization. Resetting more times can be useful since the GE objective function is non-convex

Parameters:

numResets - Number of resets of L-BFGS

setStateLabelMap

public void setStateLabelMap(StateLabelMap map)

setOptimizable

public void setOptimizable(Optimizer optimizer)

getOptimizable

public Optimizable.ByGradientValue getOptimizable(InstanceList unlabeled)

getOptimizer

public Optimizer getOptimizer(Optimizable.ByGradientValue optimizable)

train

public boolean train(InstanceList unlabeledSet,
                     int numIterations)

Description copied from class: TransducerTrainer

Train the transducer associated with this TransducerTrainer. You should be able to call this method with different trainingSet objects. Whether this causes the TransducerTrainer to combine both trainingSets or to view the second as a new alternative is at the discretion of the particular TransducerTrainer subclass involved.

Specified by:

train in class TransducerTrainer