Consider the following: Two researchers, A and B, are trying to determine whether eating fatty foods leads to heart attacks. The researchers proceed differently. Researcher A builds a model in which fatty foods may first affect X in one’s body, and if X is affected, then Y may be affected, and if Y is affected, then Z may be affected. Finally, if Z is affected, the heart is affected, and the individual has an increased probability of suffering a heart attack. Researcher B doesn’t proceed in this step-by-step fashion. She conducts an experiment to see whether people who eat many fatty foods have more, fewer, or the same number of heart attacks as people who eat few fatty foods. Which researcher’s methods have more in common with the research methodology implicit in the Keynesian transmission mechanism?

Which researcher’s methods have more in common with the research methodology implicit in the monetarist transmission mechanism? Explain your answer.