Package edu.cmu.tetrad.search.score

Class ImagesScore

java.lang.Object

edu.cmu.tetrad.search.score.ImagesScore

All Implemented Interfaces:

Score

public class ImagesScore
extends Object
implements Score

Implements a score to average results over multiple scores. This is used for the IMaGES algorithm. The idea is that one pick and algorithm that takes (only) a score as input, such as FGES or GRaSP or BOSS, and then constructs an ImagesScore (which class) with a list of datasets as input, using same object-identical variables, and feeds this Images score to this algorithm through the constructor. One then runs the algorithm to get an estimate of the structure.

Importantly, only the variables from the first score will be returned from the getVariables method, so it is up to the user to ensure that all the scores share the same (object-identical) variables.

As for all scores in Tetrad, higher scores mean more dependence, and negative scores indicate independence.

Version:

$Id: $Id

Author:

josephramsey

See Also:

• Fges
• Grasp
• Boss

Constructor Summary

Constructors

Constructor	Description
ImagesScore(List<Score> scores)	Constructs an IMaGES score using the given list of individual scores.

Method Summary

Modifier and Type	Method	Description
boolean	determines(List<Node> z, Node y)	Returns true iff the score determines the edge between x and y.
int	getMaxDegree()	Returns the max degree, by default 1000.
int	getSampleSize()	The sample size of the data.
List<Node>	getVariables()	The variables of the score.
boolean	isEffectEdge(double bump)	Returns true iff the edge between x and y is an effect edge.
double	localScore(int i)	Returns the local score of the gien node in the graph.
double	localScore(int i, int parent)	Returns the (aggregate) local score for a variable given one of its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).
double	localScore(int i, int[] parents)	Returns the (aggregate) local score for a variable given its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).
double	localScore(int i, int[] parents, int index)	Returns the (aggregate) local score for a variable given its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).
double	localScoreDiff(int x, int y, int[] z)	Returns the score difference of the graph.

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.cmu.tetrad.search.score.Score

append, getVariable, localScoreDiff, toString

Constructor Details

ImagesScore

public ImagesScore(List<Score> scores)

Constructs an IMaGES score using the given list of individual scores. These scores will be averaged to obtain the IMaGES score itself.

Parameters:

scores - The list of scores.

Method Details

localScoreDiff

public double localScoreDiff(int x,
 int y,
 int[] z)
                      throws InterruptedException

Returns the score difference of the graph.

Returns the average of the individual scores returned from each component score from their localScoreDiff methods. Score differences that are returned as undefined (NaN) are excluded from the average.

Specified by:

localScoreDiff in interface Score

Parameters:

x - A node.

y - TAhe node.

z - A set of nodes.

Returns:

The score difference.

Throws:

InterruptedException

localScore

public double localScore(int i,
 int[] parents)

Returns the (aggregate) local score for a variable given its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).

Specified by:

localScore in interface Score

Parameters:

i - The variable whose score is needed.

parents - an array of objects

Returns:

This score.

localScore

public double localScore(int i,
 int[] parents,
 int index)

Returns the (aggregate) local score for a variable given its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).

Parameters:

i - The variable whose score is needed.

parents - The indices of the parents.

index - The index of the score to use.

Returns:

This score.

localScore

public double localScore(int i,
 int parent)

Returns the (aggregate) local score for a variable given one of its parents, which is obtained by averaging the local such scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).

Specified by:

localScore in interface Score

Parameters:

i - The variable whose score is needed.

parent - a int

Returns:

This score.

localScore

public double localScore(int i)

Returns the local score of the gien node in the graph.

Returns the (aggregate) local node score, which is obtained by averaging the local scores obtained from each individual score provided in the constructor, excluding scores that are returned as undefined (which are left out of the average).

Specified by:

localScore in interface Score

Parameters:

i - A node.

Returns:

The local score.

isEffectEdge

public boolean isEffectEdge(double bump)

Returns true iff the edge between x and y is an effect edge.

Returns a judgment for FGES whether a score with the bump is for an effect edge.

Specified by:

isEffectEdge in interface Score

Parameters:

bump - The bump.

Returns:

True iff the edge between x and y is an effect edge.

getVariables

public List<Node> getVariables()

The variables of the score.

Returns the variables.

Specified by:

getVariables in interface Score

Returns:

This list.

getSampleSize

public int getSampleSize()

The sample size of the data.

Returns the sample size from the first score.

Specified by:

getSampleSize in interface Score

Returns:

This size.

getMaxDegree

public int getMaxDegree()

Returns the max degree, by default 1000.

Returns the max degree from teh first score.

Specified by:

getMaxDegree in interface Score

Returns:

The max degree.

determines

public boolean determines(List<Node> z,
 Node y)

Returns true iff the score determines the edge between x and y.

Returns the 'determines' judgment from the first score.

Specified by:

determines in interface Score

Parameters:

z - The set of nodes.

y - The node.

Returns:

True iff the score determines the edge between x and y.