CliqueNode-class {RNetica}R Documentation

Class "CliqueNode"

Description

A dummy node used to force it parents into the same clique in the junction tree. In particular, the node has a single state but its parents are listed in its clique field.

Extends

Class "NeticaNode", directly.

All reference classes extend and inherit methods from "envRefClass". Note that because this is a reference class unlike traditional S3 and S4 classes it can be destructively modified. Also fields (slots) are accessed using the ‘$’ operator.

Methods

toString

signature(x = "CliqueNode"): Provides a pretited representation.

Fields

Note these should be regarded as read-only from user code.

Name:

Object of class character giving the Netica name of the node. Must follow the IDname rules.

Netica_Node:

Object of class externalptr giving the address of the node in Netica's memory space.

Net:

Object of class NeticaBN, a back reference to the network in which this node resides.

discrete:

Always TRUE for clique nodes.

clique:

A list of NeticaNode objects which are the parents of the clique node.

Class-Based Methods

show():

Prints a description of the node.

initialize(..., clique):

Internal initializer, should not be called directly by user code. Use MakeCliqueNode instead.

The following methods are inherited (from the NeticaNode): deactivate ("NeticaNode"), isActive ("NeticaNode"), show ("NeticaNode"), clearErrors ("NeticaNode"), reportErrors ("NeticaNode"), initialize ("NeticaNode")

Note

Clique nodes only last for the R session that was used to create them. After that, they will appear like ordinary nodes. They will still be present in the network, but the special "clique" attribute will be lost.

Currently Netica only allows virtual evidence at the node level (NodeLikelihood()). I'm lobbying to get Netica to support it at the clique level as well. At which point, this function becomes extremely useful.

Author(s)

Russell Almond

References

Almond, R. G. & Mislevy, R. J. (1999) Graphical models and computerized adaptive testing. Applied Psychological Measurement, 23, 223-238.

Almond, R., Herskovits, E., Mislevy, R. J., & Steinberg, L. S. (1999). Transfer of information between system and evidence models. In Artificial Intelligence and Statistics 99, Proceedings (pp. 181–186). Morgan-Kaufmann

http://norsys.com/onLineAPIManual/index.html: See the NeticaEx function FormCliqueWith is the documentation for JointProbability_bn()

See Also

MakeCliqueNode(), NeticaNode, JointProbability(), AddLink(), JunctionTreeReport()

Examples

sess <- NeticaSession()
startSession(sess)

EMSMSystem <- ReadNetworks(file.path(library(help="RNetica")$path,
                           "sampleNets","System.dne"), session=sess)

CompileNetwork(EMSMSystem)
## Note that Skill1 and Skill2 are in different cliques
JunctionTreeReport(EMSMSystem)

Skills12 <- NetworkFindNode(EMSMSystem,c("Skill1","Skill2"))
cn <- MakeCliqueNode(Skills12)
cnclique <- GetClique(cn)

stopifnot(
  is.CliqueNode(cn),
  setequal(sapply(cnclique,NodeName),sapply(Skills12,NodeName))
)

CompileNetwork(EMSMSystem)
## Note that Skill1 and Skill2 are in different cliques
JunctionTreeReport(EMSMSystem)

DeleteNodes(cn) ## This clears the clique.

DeleteNetwork(EMSMSystem)
stopSession(sess)


[Package RNetica version 0.8-2 Index]