opendial.bn.distribs

Interface MultivariateDistribution

All Known Implementing Classes:

EmpiricalDistribution, MultivariateTable

public interface MultivariateDistribution

Representation of a multivariate probability distribution P(X1,...Xn), where X1,...Xn are random variables.

Method Summary

Modifier and Type	Method and Description
MultivariateDistribution	copy() Returns a copy of the distribution.
Assignment	getBest() Returns the value with maximum probability.
IndependentDistribution	getMarginal(java.lang.String variable) Returns the marginal probability distribution P(Xi) for a random variable Xi in X1,...Xn.
double	getProb(Assignment values) Returns the probability of a particular assignment of values.
java.util.Set<Assignment>	getValues() Returns the set of possible assignments for the random variables.
java.util.Set<java.lang.String>	getVariables() Returns the names of the random variables in the distribution
void	modifyVariableId(java.lang.String oldId, java.lang.String newId) Modifies the variable identifier in the distribution
boolean	pruneValues(double threshold) Prunes all values assignment whose probability falls below the threshold.
Assignment	sample() Returns a sample assignment for X1,...Xn.
MultivariateTable	toDiscrete() Returns a representation of the distribution as a multivariate table.

Method Detail

getVariables

java.util.Set<java.lang.String> getVariables()

Returns the names of the random variables in the distribution

Returns:

the set of variable names.

getValues

java.util.Set<Assignment> getValues()

Returns the set of possible assignments for the random variables.

Returns:

the set of possible assignment

getProb

double getProb(Assignment values)

Returns the probability of a particular assignment of values.

Parameters:

values - the assignment of values to X1,...Xn.

Returns:

the corresponding probability

sample

Assignment sample()

Returns a sample assignment for X1,...Xn.

Returns:

the sampled assignment

getMarginal

IndependentDistribution getMarginal(java.lang.String variable)

Returns the marginal probability distribution P(Xi) for a random variable Xi in X1,...Xn.

Parameters:

variable - the random variable Xi

Returns:

the marginal distribution P(Xi)

modifyVariableId

void modifyVariableId(java.lang.String oldId,
                      java.lang.String newId)

Modifies the variable identifier in the distribution

Parameters:

oldId - the old identifier

newId - the new identifier

toDiscrete

MultivariateTable toDiscrete()

Returns a representation of the distribution as a multivariate table.

Returns:

the multivariate table.

copy

MultivariateDistribution copy()

Returns a copy of the distribution.

Returns:

the copy.

pruneValues

boolean pruneValues(double threshold)

Prunes all values assignment whose probability falls below the threshold.

Parameters:

threshold - the threshold to apply

Returns:

true if at least one value has been removed, false otherwise

getBest

Assignment getBest()

Returns the value with maximum probability.

Returns:

the value with maximum probability