And the set dseparations the dag subset ind

559  

X  W  X  
Y  Z  Y  
(a)  (b) 
Example 10.13 Suppose V = {X, Y, Z, W} and
IND = {I({X}, {Z}{Y, W}), I({Y }, {W}{X, Z})}.
560  X  

H1 


Y 

W 
X  Y  Z  W 

Figure 10.15: Given V = {X, Y, Z, W, T} and IND consists of the dseparations in the DAG in (a) restricted to these variables, Algorithm 10.4 will produce the DAG in (b) or one with W → T instead of W ← T.
pattern containing the dseparations. The next example shows a situation in which the output of Algorithm 10.4 is a DAG, but the set of dseparations in the DAG is not a subset of IND.