Figure 3

Illustration of the procedures in establishing undirected, directed, or partially directed graphs. (A) If correlation Cor(i, j) is significant, draw an edge between node i and node j (i, j ∈ (x, y, z)). (B) The conditional correlation Cor(x, y|z) is insignificant, remove the edge (x, y). (C) Using other information to select one or few causal models that are consistent with the data.