Package edu.cmu.tetrad.sem

Class SemPm

java.lang.Object

edu.cmu.tetrad.sem.SemPm

All Implemented Interfaces:

Pm, TetradSerializable, Serializable

public final class SemPm
extends Object
implements Pm, TetradSerializable

Parametric model for Structural Equation Models.

Note: Could not get a copy constructor to work properly, so to copy SemPm objects, use object serialization--e.g. java.rmu.MarshalledObject.

Version:

$Id: $Id

Author:

Donald Crimbchin, josephramsey

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
SemPm(Graph graph)	Constructs a BayesPm from the given Graph, which must be convertible first into a ProtoSemGraph and then into a SemGraph.
SemPm(SemGraph graph)	Constructs a new SemPm from the given SemGraph.
SemPm(SemPm semPm)	Copy constructor.

Method Summary

Modifier and Type	Method	Description
void	fixLatentErrorVariances()	fixLatentErrorVariances.
void	fixOneLoadingPerLatent()	fixOneLoadingPerLatent.
Parameter	getCoefficientParameter(Node nodeA, Node nodeB)	getCoefficientParameter.
Parameter	getCovarianceParameter(Node nodeA, Node nodeB)	getCovarianceParameter.
int	getDof()	getDof.
List<Parameter>	getFreeParameters()	getFreeParameters.
SemGraph	getGraph()	Getter for the field graph.
List<Node>	getLatentNodes()	getLatentNodes.
Parameter	getMeanParameter(Node node)	getMeanParameter.
List<Node>	getMeasuredNodes()	getMeasuredNodes.
String[]	getMeasuredVarNames()	getMeasuredVarNames.
ParamComparison	getParamComparison(Parameter a, Parameter b)	getParamComparison.
Parameter	getParameter(Node nodeA, Node nodeB)	getParameter.
Parameter	getParameter(String name)	getParameter.
List<Parameter>	getParameters()	Getter for the field parameters.
List<Node>	getVariableNodes()	Getter for the field variableNodes.
Parameter	getVarianceParameter(Node node)	Return the parameter for the variance of the error term for the given node, which is the variance of the node if the node is an error term, and the variance of the node's error term if not.
static SemPm	serializableInstance()	Generates a simple exemplar of this class to test serialization.
void	setParamComparison(Parameter a, Parameter b, ParamComparison comparison)	Sets the comparison of parameter a to parameter b.
String	toString()	toString.

Methods inherited from class java.lang.Object

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

Constructor Details

SemPm

public SemPm(Graph graph)

Constructs a BayesPm from the given Graph, which must be convertible first into a ProtoSemGraph and then into a SemGraph.

Parameters:

graph - a Graph object

SemPm

public SemPm(SemGraph graph)

Constructs a new SemPm from the given SemGraph.

Parameters:

graph - a SemGraph object

SemPm

public SemPm(SemPm semPm)

Copy constructor.

Parameters:

semPm - a SemPm object

Method Details

serializableInstance

public static SemPm serializableInstance()

Generates a simple exemplar of this class to test serialization.

Returns:

a SemPm object

fixLatentErrorVariances

public void fixLatentErrorVariances()

fixLatentErrorVariances.

fixOneLoadingPerLatent

public void fixOneLoadingPerLatent()

fixOneLoadingPerLatent.

getGraph

public SemGraph getGraph()

Getter for the field graph.

Returns:

the structural model graph this SEM PM is using.

getParameters

public List<Parameter> getParameters()

Getter for the field parameters.

Returns:

a list of all the freeParameters, including variance, covariance, coefficient, and mean freeParameters.

getVariableNodes

public List<Node> getVariableNodes()

Getter for the field variableNodes.

Returns:

the list of variable nodes--that is, node that are not error nodes.

getMeasuredNodes

public List<Node> getMeasuredNodes()

getMeasuredNodes.

Returns:

the list of measured variableNodes.

getLatentNodes

public List<Node> getLatentNodes()

getLatentNodes.

Returns:

the list of latent variableNodes.

getParameter

public Parameter getParameter(String name)

getParameter.

Parameters:

name - a String object

Returns:

the first parameter encountered with the given name, or null if there is no such parameter.

getParameter

public Parameter getParameter(Node nodeA,
 Node nodeB)

getParameter.

Parameters:

nodeA - a Node object

nodeB - a Node object

Returns:

a Parameter object

getVarianceParameter

public Parameter getVarianceParameter(Node node)

Return the parameter for the variance of the error term for the given node, which is the variance of the node if the node is an error term, and the variance of the node's error term if not.

Parameters:

node - a Node object

Returns:

a Parameter object

getCovarianceParameter

public Parameter getCovarianceParameter(Node nodeA,
 Node nodeB)

getCovarianceParameter.

Parameters:

nodeA - a Node object

nodeB - a Node object

Returns:

a Parameter object

getCoefficientParameter

public Parameter getCoefficientParameter(Node nodeA,
 Node nodeB)

getCoefficientParameter.

Parameters:

nodeA - a Node object

nodeB - a Node object

Returns:

a Parameter object

getMeanParameter

public Parameter getMeanParameter(Node node)

getMeanParameter.

Parameters:

node - a Node object

Returns:

a Parameter object

getMeasuredVarNames

public String[] getMeasuredVarNames()

getMeasuredVarNames.

Returns:

the list of measured variable names in the order in which they appear in the list of nodes. (This order is fixed.)

getParamComparison

public ParamComparison getParamComparison(Parameter a,
 Parameter b)

getParamComparison.

Parameters:

a - a Parameter object

b - a Parameter object

Returns:

the comparison of parameter a to parameter b.

setParamComparison

public void setParamComparison(Parameter a,
 Parameter b,
 ParamComparison comparison)

Sets the comparison of parameter a to parameter b.

Parameters:

a - a Parameter object

b - a Parameter object

comparison - a ParamComparison object

getFreeParameters

public List<Parameter> getFreeParameters()

getFreeParameters.

Returns:

a List object

getDof

public int getDof()

getDof.

Returns:

the degrees of freedom for the model.

toString

public String toString()

toString.

Overrides:

toString in class Object

Returns:

a String object