a causal diagram, then both the thinking that goes into the construction and the interpretation of the final diagram change. In the construction phase, we need to examine each variable, say C, and ask ourselves which other variables it “listens” to before choosing its value. The chain structure A → B → C means that B listens to A only, C listens to B only, and A listens to no one; that is, it is determined by external forces that are not part of our model.
