de.jungblut.ner

Class ConditionalLikelihoodCostFunction

java.lang.Object

de.jungblut.ner.ConditionalLikelihoodCostFunction

All Implemented Interfaces:

CostFunction

public final class ConditionalLikelihoodCostFunction
extends Object
implements CostFunction

Conditional likelihood cost function, used in a maximum entropy markov model to optimize the weights.

Author:

thomas.jungblut

Constructor Summary

Constructors

Constructor and Description
ConditionalLikelihoodCostFunction(de.jungblut.math.DoubleMatrix features, de.jungblut.math.DoubleMatrix outcome)

Method Summary

Modifier and Type	Method and Description
CostGradientTuple	evaluateCost(de.jungblut.math.DoubleVector input) Evaluation for the cost function to retrieve cost and gradient.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConditionalLikelihoodCostFunction

public ConditionalLikelihoodCostFunction(de.jungblut.math.DoubleMatrix features,
                                         de.jungblut.math.DoubleMatrix outcome)

Method Detail

evaluateCost

public CostGradientTuple evaluateCost(de.jungblut.math.DoubleVector input)

Description copied from interface: CostFunction

Evaluation for the cost function to retrieve cost and gradient.

Specified by:

evaluateCost in interface CostFunction

Parameters:

input - a given input vector

Returns:

a tuple consists of J (cost) and a vector X which is the gradient of the input.