Package opennlp.tools.ml.naivebayes

Class LogProbabilities<T>

java.lang.Object

opennlp.tools.ml.naivebayes.Probabilities<T>

opennlp.tools.ml.naivebayes.LogProbabilities<T>

Type Parameters:

T - the label (category) class

public class LogProbabilities<T>
extends Probabilities<T>

Class implementing the probability distribution over labels returned by a classifier as a log of probabilities.

This is necessary because floating point precision in Java does not allow for high-accuracy representation of very low probabilities such as would occur in a text categorizer.

See Also:

Probabilities

Constructor Summary

Constructors

Constructor	Description
LogProbabilities()

Method Summary

Modifier and Type	Method	Description
void	addIn(T t, double probability, int count)	Compounds the existing probability mass on the label t with the new probability passed in to the method.
void	discardCountsBelow(double i)
Double	get(T t)
Map<T,Double>	getAll()
Double	getLog(T t)
T	getMax()
void	set(T t, double probability)	Assigns a probability to a label t, discarding any previously assigned probability.
void	set(T t, Probability<T> probability)	Assigns a probability to a label t, discarding any previously assigned probability.
void	setIfLarger(T t, double probability)	Assigns a probability to a label t, discarding any previously assigned probability, if the new probability is greater than the old one.
void	setLog(T t, double probability)	Assigns a log probability to a label t, discarding any previously assigned probability.

Methods inherited from class opennlp.tools.ml.naivebayes.Probabilities

getConfidence, getKeys, getMaxValue, setConfidence, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

LogProbabilities

public LogProbabilities()

Method Detail

set

public void set(T t,
                double probability)

Assigns a probability to a label t, discarding any previously assigned probability.

Overrides:

set in class Probabilities<T>

Parameters:

t - The label to which the probability is being assigned.

probability - The probability to assign.

set

public void set(T t,
                Probability<T> probability)

Assigns a probability to a label t, discarding any previously assigned probability.

Overrides:

set in class Probabilities<T>

Parameters:

t - The label to which the probability is being assigned.

probability - The Probability to assign.

setIfLarger

public void setIfLarger(T t,
                        double probability)

Assigns a probability to a label t, discarding any previously assigned probability, if the new probability is greater than the old one.

Overrides:

setIfLarger in class Probabilities<T>

Parameters:

t - The label to which the probability is being assigned.

probability - The probability to assign.

setLog

public void setLog(T t,
                   double probability)

Assigns a log probability to a label t, discarding any previously assigned probability.

Overrides:

setLog in class Probabilities<T>

Parameters:

t - The label to which the log probability is being assigned.

probability - The log probability to assign.

addIn

public void addIn(T t,
                  double probability,
                  int count)

Compounds the existing probability mass on the label t with the new probability passed in to the method.

Overrides:

addIn in class Probabilities<T>

Parameters:

t - The label whose probability mass is being updated.

probability - The probability weight to add.

count - The amplifying factor for the probability compounding.

get

public Double get(T t)

Overrides:

get in class Probabilities<T>

Parameters:

t - The label whose probability shall be returned.

Returns:

Retrieves the probability associated with the label t.

getLog

public Double getLog(T t)

Overrides:

getLog in class Probabilities<T>

Parameters:

t - The label whose log probability shall be returned.

Returns:

Retrieves the log probability associated with the label t.

discardCountsBelow

public void discardCountsBelow(double i)

Overrides:

discardCountsBelow in class Probabilities<T>

getAll

public Map<T,Double> getAll()

Overrides:

getAll in class Probabilities<T>

Returns:

Retrieves a Map of all labels and their probabilities.

getMax

public T getMax()

Overrides:

getMax in class Probabilities<T>

Returns:

Retrieves the label that has the highest associated probability