proportional to the joint between all these variables x2 comma Z 0 Z 1 Z 2 Z 3 Z 4 now we don't directly have this kind of joint available what we have available here is something of the form that involves all of these variables so all the conditionals multiplied together in that graph over there is what we have available and then some variables we're not going to care about X 0 X 1 X 3 and X 4 we don't care about we will write out the full joint over all 10 variables and then sum out the four variables we don't care about so what's the fool