One of the first thing that any so-called "macro-economist" does when studying a phenomenon, is to postulate a deterministic model in which there is no choice and all economic costs are thus zero. That is, whenever they introduce mathematical tools, which they do so as to pose as physics-like hard scientists, they begin by negating the very essence of economics: the notion of economic cost. They are actually based upon an epistemology that explicitly denies individuals the essence of their human nature: the ability to make relevant choices. This is true of all economists from all schools of economics, save the few libertarians from the austrian school and its direct relatives. And the crooks include the neo-classical schools (that dictates the economic orthodoxy in most rich countries), and the keynesian and marxist schools (that dictate the economic orthodoxy in France and other socialist countries). No wonder why all these schools of economics produce only lies, in the form of deceitful statistics and bogus assumptions smuggled under the veil of meaningless mathematics.
If mathematical models were to be used at all in economic science, we would need non-deterministic models, replacing (neo)classical economics with quantum economics. And then we'd find that we're not able to even imagine the Feynman diagrams of all possible interactions over which to integrate our economic functions, because the relevant interactions that will take place between agents are precisely those based upon information that others don't have, including the person trying to build the model.
PS: Oh yes, one particular crook from the top of the Establishment just called me
ridiculous for rejecting the results of so many
scientific studies based on empiricism. You may find more about the fraud that is empiricism in social sciences by reading e.g. Hoppe,
whom you may hear in this course.