cc.mallet.grmm.inference
Class AbstractInferencer

java.lang.Object
  cc.mallet.grmm.inference.AbstractInferencer

All Implemented Interfaces:

Inferencer, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

AbstractBeliefPropagation, BruteForceInferencer, JunctionTreeInferencer, ParentChildGBP, SamplingInferencer, VariableElimination

public abstract class AbstractInferencer
extends java.lang.Object
implements Inferencer, java.lang.Cloneable

Abstract base class for inferencers. This simply throws an UnsupportedOperationException for all methods, which is useful for subclasses that want to implement only specific inference functionality. Created: Mon Oct 6 17:01:21 2003

Version:

$Id: AbstractInferencer.java,v 1.1 2007/10/22 21:37:49 mccallum Exp $

Author:

Charles Sutton

See Also:

Serialized Form

Constructor Summary

AbstractInferencer()

Method Summary

abstract void	computeMarginals(FactorGraph fg) Computes marginal distributions for a factor graph.
void	dump()
Inferencer	duplicate()
double	lookupJoint(Assignment assn) Returns the joint probability of a given assignment, computed in some factorized fashion.
double	lookupLogJoint(Assignment assn) Returns the natural logarithm of the joint probability of a given assignment, computed in some factorized fashion.
abstract Factor	lookupMarginal(Variable variable) Returns the computed marginal of a given variable.
Factor	lookupMarginal(VarSet c) Returns the computed marginal of a given clique in a graph.
double	query(FactorGraph mdl, Assignment assn) Computes the marginal probability of a given assignment to a small number of model variables.
void	reportTime() Outputs some measure of the total time spent in this inferencer.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractInferencer

public AbstractInferencer()

Method Detail

computeMarginals

public abstract void computeMarginals(FactorGraph fg)

Description copied from interface: Inferencer

Computes marginal distributions for a factor graph.

Specified by:

computeMarginals in interface Inferencer

lookupJoint

public double lookupJoint(Assignment assn)

Description copied from interface: Inferencer

Returns the joint probability of a given assignment, computed in some factorized fashion. Before using this method, computeMarginals must have been previously called on the graphical model that contains the variables of assn.

Specified by:

lookupJoint in interface Inferencer

See Also:

Inferencer.computeMarginals(cc.mallet.grmm.types.FactorGraph), #computeMarginals(JunctionTree)

lookupLogJoint

public double lookupLogJoint(Assignment assn)

Description copied from interface: Inferencer

Returns the natural logarithm of the joint probability of a given assignment, computed in some factorized fashion. Before using this method, computeMarginals must have been previously called on the graphical model that contains the variables of assn.

This method is less likely to underflow than Math.log (lookupJoint (assn)).

Specified by:

lookupLogJoint in interface Inferencer

See Also:

Inferencer.computeMarginals(cc.mallet.grmm.types.FactorGraph), #computeMarginals(JunctionTree)

lookupMarginal

public Factor lookupMarginal(VarSet c)

Description copied from interface: Inferencer

Returns the computed marginal of a given clique in a graph. Before using this method, computeMarginals must have been previously called on the graphical model that contains the clique.

Specified by:

lookupMarginal in interface Inferencer

See Also:

Inferencer.computeMarginals(cc.mallet.grmm.types.FactorGraph), #computeMarginals(JunctionTree)

query

public double query(FactorGraph mdl,
                    Assignment assn)

Description copied from interface: Inferencer

Computes the marginal probability of a given assignment to a small number of model variables. This may require one run of computeMarginals() for each variable in the assignment; if the assigment has many variables, it may be more efficient to use lookupJoint.

Specified by:

query in interface Inferencer

lookupMarginal

public abstract Factor lookupMarginal(Variable variable)

Description copied from interface: Inferencer

Returns the computed marginal of a given variable. Before using this method, computeMarginals must have been previously called on the graphical model that contains v.

Specified by:

lookupMarginal in interface Inferencer

See Also:

Inferencer.computeMarginals(FactorGraph)

duplicate

public Inferencer duplicate()

Specified by:

duplicate in interface Inferencer

dump

public void dump()

Specified by:

dump in interface Inferencer

reportTime

public void reportTime()

Description copied from interface: Inferencer

Outputs some measure of the total time spent in this inferencer.

Specified by:

reportTime in interface Inferencer