public static Graph bestGuessCycleOrientation(Graph graph, IndependenceTest test) {
while (true) {
List<Node> cycle = GraphUtils.directedCycle(graph);
if (cycle == null) {
break;
}
LinkedList<Node> _cycle = new LinkedList<Node>(cycle);
Node first = _cycle.getFirst();
Node last = _cycle.getLast();
_cycle.addFirst(last);
_cycle.addLast(first);
int _j = -1;
double minP = Double.POSITIVE_INFINITY;
for (int j = 1; j < _cycle.size() - 1; j++) {
int i = j - 1;
int k = j + 1;
Node x = test.getVariable(_cycle.get(i).getName());
Node y = test.getVariable(_cycle.get(j).getName());
Node z = test.getVariable(_cycle.get(k).getName());
test.isIndependent(x, z, Collections.singletonList(y));
System.out.println("Testing " + x + " _||_ " + z + " | " + y);
double p = test.getPValue();
System.out.println("p = " + p);
if (p < minP) {
_j = j;
minP = p;
}
}
Node x = _cycle.get(_j - 1);
Node y = _cycle.get(_j);
Node z = _cycle.get(_j + 1);
graph.removeEdge(x, y);
graph.removeEdge(z, y);
graph.addDirectedEdge(x, y);
graph.addDirectedEdge(z, y);
}
return graph;
}
