org.joone.engine.learning
Class FahlmanTeacherSynapse

java.lang.Object
  org.joone.engine.Synapse
      org.joone.engine.learning.AbstractTeacherSynapse
          org.joone.engine.learning.TeacherSynapse
              org.joone.engine.learning.FahlmanTeacherSynapse

All Implemented Interfaces:

java.io.Serializable, InputPatternListener, Learnable, LearnableSynapse, NeuralElement, OutputPatternListener, Inspectable

public class FahlmanTeacherSynapse
extends TeacherSynapse

This class extends the normal Teacher synapse and implements the Fahlman 40-20-40 criterion (the values can be changed). This teacher makes only sense in case of binary outputs.

In case of the default values (40-20-40) and considering [0,1] binary outputs the criterion is fullfilled if for all patterns the output is - within [0, 0.4] in case the desired output is 0 - within [0.6, 1] in case the desired output is 1.

More about this criterion can be found at http://citeseer.ist.psu.edu/fahlman88empirical.html.

Author:

Boris Jansen

See Also:

Serialized Form

Field Summary

static java.lang.String	CRITERION Constant to indicate (key) the parameter for checking (in the monitor object) if the criterion has been forfilled or not.
protected static ILogger	log Logger

Fields inherited from class org.joone.engine.learning.TeacherSynapse

GlobalError

Fields inherited from class org.joone.engine.learning.AbstractTeacherSynapse

currEpoch, desired, error, lastErrorPatternReady, net

Fields inherited from class org.joone.engine.Synapse

array, b_pattern, bitems, bouts, count, enabled, fwdLock, inps, items, learnable, m_batch, m_pattern, myLearner, outs, revLock

Constructor Summary

FahlmanTeacherSynapse()
Creates a new instance of FahlmanTeacherSynapse

Method Summary

double	calculateError(double aDesired, double anOutput, int anIndex) Calculates the error to be backpropaged for a single output neuron.
double	getLowerBit() Gets the lower bit value.
double	getLowerBitPercentage() Gets the lower bit percentage.
double	getUpperBit() Gets the upper bit value.
double	getUpperBitPercentage() Gets the upper bit percentage.
void	setLowerBit(double aValue) Sets the lower bit.
void	setLowerBitPercentage(double aValue) Sets the lower bit percentage.
void	setUpperBit(double aValue) Sets the upper bit.
void	setUpperBitPercentage(double aValue) Sets the upper bit percentage.

Methods inherited from class org.joone.engine.learning.TeacherSynapse

calculateGlobalError, fwdPut

Methods inherited from class org.joone.engine.learning.AbstractTeacherSynapse

backward, check, constructErrorPattern, epochFinished, forward, fwdGet, getDesired, getLastErrorPattern, getSeenPatterns, incSeenPatterns, init, isFirstTime, isLastErrorPatternReady, netStoppedError, pushError, readResolve, reset, resetInput, revGet, revPut, setArrays, setDesired, setDimensions, setFirstTime, setInputDimension, setMonitor, setSeenPatterns, stopTheNet

Methods inherited from class org.joone.engine.Synapse

addNoise, canCountSteps, fwdPattern_consume, fwdPattern_produce, getCount, getFwdLock, getIgnoreBefore, getInputDimension, getLearner, getLearningRate, getMomentum, getMonitor, getName, getOutputDimension, getRevLock, getSynapseNameSafely, getWeights, initLearner, InspectableTitle, Inspections, isEnabled, isInputFull, isLoopBack, isOutputFull, randomize, revPattern_consume, revPattern_produce, setEnabled, setIgnoreBefore, setInputFull, setLearningRate, setLoopBack, setMomentum, setName, setOutputDimension, setOutputFull, setWeights, warnLogger, warnLogger

Methods inherited from class java.lang.Object

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

Field Detail

CRITERION

public static final java.lang.String CRITERION

Constant to indicate (key) the parameter for checking (in the monitor object) if the criterion has been forfilled or not.

See Also:

Constant Field Values

log

protected static final ILogger log

Logger

Constructor Detail

FahlmanTeacherSynapse

public FahlmanTeacherSynapse()

Creates a new instance of FahlmanTeacherSynapse

Method Detail

setUpperBit

public void setUpperBit(double aValue)

Sets the upper bit.

Parameters:

aValue - sets the upper bit to aValue.

getUpperBit

public double getUpperBit()

Gets the upper bit value.

Returns:

the upper bit value.

setLowerBit

public void setLowerBit(double aValue)

Sets the lower bit.

Parameters:

aValue - sets the lower bit to aValue.

getLowerBit

public double getLowerBit()

Gets the lower bit value.

Returns:

the lower bit value.

setUpperBitPercentage

public void setUpperBitPercentage(double aValue)

Sets the upper bit percentage.

Parameters:

aValue - sets the upper bit percentage to aValue.

getUpperBitPercentage

public double getUpperBitPercentage()

Gets the upper bit percentage.

Returns:

the upper bit percentage.

setLowerBitPercentage

public void setLowerBitPercentage(double aValue)

Sets the lower bit percentage.

Parameters:

aValue - sets the lower bit percentage to aValue.

getLowerBitPercentage

public double getLowerBitPercentage()

Gets the lower bit percentage.

Returns:

the lower bit percentage.

calculateError

public double calculateError(double aDesired,
                             double anOutput,
                             int anIndex)

Description copied from class: AbstractTeacherSynapse

Calculates the error to be backpropaged for a single output neuron. (The function should also update the global error internally).

Overrides:

calculateError in class TeacherSynapse

Parameters:

aDesired - the desired output

anOutput - the actual output of a single neuron

anIndex - the index of the output neuron

Returns:

the error to be back propagated