/** Orients according to background knowledge */
private void fciOrientbk(IKnowledge bk, Graph graph, List<Node> variables) {
logger.log("info", "Starting BK Orientation.");
for (Iterator<KnowledgeEdge> it = bk.forbiddenEdgesIterator(); it.hasNext(); ) {
KnowledgeEdge edge = it.next();
// match strings to variables in the graph.
Node from = SearchGraphUtils.translate(edge.getFrom(), variables);
Node to = SearchGraphUtils.translate(edge.getTo(), variables);
if (from == null || to == null) {
continue;
}
if (graph.getEdge(from, to) == null) {
continue;
}
// Orient to*->from
graph.setEndpoint(to, from, Endpoint.ARROW);
graph.setEndpoint(from, to, Endpoint.CIRCLE);
changeFlag = true;
logger.log(
"knowledgeOrientation",
SearchLogUtils.edgeOrientedMsg("Knowledge", graph.getEdge(from, to)));
}
for (Iterator<KnowledgeEdge> it = bk.requiredEdgesIterator(); it.hasNext(); ) {
KnowledgeEdge edge = it.next();
// match strings to variables in this graph
Node from = SearchGraphUtils.translate(edge.getFrom(), variables);
Node to = SearchGraphUtils.translate(edge.getTo(), variables);
if (from == null || to == null) {
continue;
}
if (graph.getEdge(from, to) == null) {
continue;
}
graph.setEndpoint(to, from, Endpoint.TAIL);
graph.setEndpoint(from, to, Endpoint.ARROW);
changeFlag = true;
logger.log(
"knowledgeOrientation",
SearchLogUtils.edgeOrientedMsg("Knowledge", graph.getEdge(from, to)));
}
logger.log("info", "Finishing BK Orientation.");
}
/**
* Step C of PC; orients colliders using specified sepset. That is, orients x *-* y *-* z as x *->
* y <-* z just in case y is in Sepset({x, z}).
*/
public Map<Triple, Double> findCollidersUsingSepsets(
SepsetProducer sepsetProducer, Graph graph, boolean verbose, IKnowledge knowledge) {
TetradLogger.getInstance().log("details", "Starting Collider Orientation:");
Map<Triple, Double> colliders = new HashMap<>();
System.out.println("Looking for colliders");
List<Node> nodes = graph.getNodes();
for (Node b : nodes) {
List<Node> adjacentNodes = graph.getAdjacentNodes(b);
if (adjacentNodes.size() < 2) {
continue;
}
ChoiceGenerator cg = new ChoiceGenerator(adjacentNodes.size(), 2);
int[] combination;
while ((combination = cg.next()) != null) {
Node a = adjacentNodes.get(combination[0]);
Node c = adjacentNodes.get(combination[1]);
// Skip triples that are shielded.
if (graph.isAdjacentTo(a, c)) {
continue;
}
List<Node> sepset = sepsetProducer.getSepset(a, c);
if (sepset == null) continue;
// if (sepsetProducer.getPValue() < 0.5) continue;
if (!sepset.contains(b)) {
if (verbose) {
// boolean dsep = this.dsep.isIndependent(a, c);
// System.out.println("QQQ p = " + independenceTest.getPValue() +
// " " + dsep);
System.out.println(
"\nCollider orientation <" + a + ", " + b + ", " + c + "> sepset = " + sepset);
}
colliders.put(new Triple(a, b, c), sepsetProducer.getPValue());
TetradLogger.getInstance()
.log("colliderOrientations", SearchLogUtils.colliderOrientedMsg(a, b, c, sepset));
}
}
}
TetradLogger.getInstance().log("details", "Finishing Collider Orientation.");
System.out.println("Done finding colliders");
return colliders;
}
/** Tests to see if d separation facts are symmetric. */
public void testDSeparation() {
EdgeListGraphSingleConnections graph =
new EdgeListGraphSingleConnections(
new Dag(GraphUtils.randomGraph(7, 0, 7, 30, 15, 15, true)));
System.out.println(graph);
List<Node> nodes = graph.getNodes();
int depth = -1;
for (int i = 0; i < nodes.size(); i++) {
for (int j = i + 1; j < nodes.size(); j++) {
Node x = nodes.get(i);
Node y = nodes.get(j);
List<Node> theRest = new ArrayList<Node>(nodes);
theRest.remove(x);
theRest.remove(y);
DepthChoiceGenerator gen = new DepthChoiceGenerator(theRest.size(), depth);
int[] choice;
while ((choice = gen.next()) != null) {
List<Node> z = new LinkedList<Node>();
for (int k = 0; k < choice.length; k++) {
z.add(theRest.get(choice[k]));
}
if (graph.isDSeparatedFrom(x, y, z) != graph.isDSeparatedFrom(y, x, z)) {
fail(
SearchLogUtils.independenceFact(x, y, z)
+ " should have same d-sep result as "
+ SearchLogUtils.independenceFact(y, x, z));
}
}
}
}
}