Package edu.cmu.tetrad.search

Class IndTestIod

java.lang.Object

edu.cmu.tetrad.search.IndTestIod

All Implemented Interfaces:

IndependenceTest

public class IndTestIod
extends Object
implements IndependenceTest

Checks independence results by listing all tests with those variables, testing each one, and returning the resolution of these test results. The reference is here:

Tillman, R., & Spirtes, P. (2011, June). Learning equivalence classes of acyclic models with latent and selection variables from multiple datasets with overlapping variables. In Proceedings of the Fourteenth International Conference on Artificial Intelligence and Statistics (pp. 3-15). JMLR Workshop and Conference Proceedings.

The idea of this implementation is that one initializes this test with multiple independence tests (for multiple datasets), then a call to the independence check method for X _||_ Y | Z list the independence tests from among these, calls each and gets a p-value, then uses a resolution method (such as Fisher's) to resolve these p-values.

Based on work by Rob Tillman, Peter Spirtes, and referencing earlier work by David Danks.

Version:

$Id: $Id

Author:

josephramsey

Constructor Summary

Constructors

Constructor	Description
IndTestIod(List<IndependenceTest> tests)	Constructs a new pooled independence test from the given list of independence tests.

Method Summary

Modifier and Type	Method	Description
IndependenceResult	checkIndependence(Node x, Node y, Set<Node> z)	Checks the independence between two nodes given a set of nodes.
boolean	determines(List<Node> z, Node x)	Determines whether the variables in z determine x.
double	getAlpha()	Returns the significance level of the independence test.
DataSet	getData()	getData.
Node	getNode(Node variable)	Return the node associated with the given variable in the graph.
Node	getVariable(Node node)	Returns the variable associated with the given node in the graph.
Node	getVariable(String name)	Retrieves a variable with the given name.
List<Node>	getVariables()	Returns the list of TetradNodes over which this independence checker is capable of determining independence relations-- that is, all the variables in the given graph or the given data set.
IndependenceTest	indTestSubset(List<Node> vars)	Calculates the independence test for a subset of variables.
boolean	isVerbose()	Returns true if the test is verbose.
void	setAlpha(double alpha)	Sets the significance level.
void	setVerbose(boolean verbose)	Sets whether this test will print verbose output.
String	toString()	Returns a string representation of this test.

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.cmu.tetrad.search.IndependenceTest

checkIndependence, determines, getCov, getDataSets, getSampleSize, getVariableNames

Constructor Details

IndTestIod

public IndTestIod(List<IndependenceTest> tests)

Constructs a new pooled independence test from the given list of independence tests.

Parameters:

tests - a List object

Method Details

indTestSubset

public IndependenceTest indTestSubset(List<Node> vars)

Calculates the independence test for a subset of variables.

Specified by:

indTestSubset in interface IndependenceTest

Parameters:

vars - The sublist of variables.

Returns:

The independence test result.

Throws:

UnsupportedOperationException - if this method is not implemented.

checkIndependence

public IndependenceResult checkIndependence(Node x,
 Node y,
 Set<Node> z)
                                     throws InterruptedException

Checks the independence between two nodes given a set of nodes.

Specified by:

checkIndependence in interface IndependenceTest

Parameters:

x - The first node.

y - The second node.

z - The set of nodes.

Returns:

The result of the independence test.

Throws:

InterruptedException

See Also:

• IndependenceResult

getVariables

public List<Node> getVariables()

Returns the list of TetradNodes over which this independence checker is capable of determining independence relations-- that is, all the variables in the given graph or the given data set.

Specified by:

getVariables in interface IndependenceTest

Returns:

This list.

determines

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

Determines whether the variables in z determine x.

Parameters:

z - The list of nodes to search.

x - The node to check for containment.

Returns:

True if the node is contained in the list, false otherwise.

getAlpha

public double getAlpha()

Description copied from interface: IndependenceTest

Returns the significance level of the independence test.

Specified by:

getAlpha in interface IndependenceTest

Returns:

This level.

Throws:

UnsupportedOperationException - since the method is not implemented.

setAlpha

public void setAlpha(double alpha)

Description copied from interface: IndependenceTest

Sets the significance level.

Specified by:

setAlpha in interface IndependenceTest

Parameters:

alpha - This level.

Throws:

UnsupportedOperationException - since the method is not implemented.

getVariable

public Node getVariable(String name)

Retrieves a variable with the given name.

Specified by:

getVariable in interface IndependenceTest

Parameters:

name - the name of the variable

Returns:

the variable with the given name

Throws:

IllegalArgumentException - if the variable is not found

getVariable

public Node getVariable(Node node)

Returns the variable associated with the given node in the graph.

Parameters:

node - a Node object

Returns:

This variable.

getNode

public Node getNode(Node variable)

Return the node associated with the given variable in the graph.

Parameters:

variable - a Node object

Returns:

This node.

toString

public String toString()

Returns a string representation of this test.

Specified by:

toString in interface IndependenceTest

Overrides:

toString in class Object

Returns:

This string.

getData

public DataSet getData()

Description copied from interface: IndependenceTest

getData.

Specified by:

getData in interface IndependenceTest

Returns:

The data model for the independence test, either a DataSet or a CovarianceMatrix.

Throws:

UnsupportedOperationException - since the method is not implemented.

See Also:

• DataSet
• ICovarianceMatrix
• DataModel

isVerbose

public boolean isVerbose()

Returns true if the test is verbose.

Specified by:

isVerbose in interface IndependenceTest

Returns:

True, if so.

setVerbose

public void setVerbose(boolean verbose)

Sets whether this test will print verbose output.

Specified by:

setVerbose in interface IndependenceTest

Parameters:

verbose - True, if so.