On Classifying Academic Research
| Peter Klein |
Should academic work be classified primarily by discipline, or by problem? Within disciplines, do we start with theory versus application, micro versus macro, historical versus contemporary, or something else? Of course, there may be no single “optimal” classification scheme, but how we think about organizing research in our field says something about how we view the nature, contributions, and problems in the field.
There’s a very interesting discussion of this subject in the History of Economics Playground blog, focusing on the evolution of the Journal of Economic Literature codes used by economists (parts 1, 2, and 3). I particularly liked Beatrice Cherrier’s analysis of the AEA’s decision to drop “theory” as a separate category. The Machlup–Hutchison–Rothbard exchange helps establish the context.
[T]he seemingly administrative task of devising new categories threw AEA officials, in particular AER editor Bernard Haley and former AER interim editor Fritz Machlup, into heated debates over the nature and relationships of theoretical and empirical work.
Machlup campaigned for a separate “Abstract Economic Theory” top category. At the time of the revision, he was engaged in methodological work, striving to find a third way between Terence Hutchison’s “ultraempiricism,” and the “extreme a priorism” of his former mentor, Ludwig Von Mises (see Blaug, ch.4). He believed it was possible to differentiate between “fundamental (heuristic) hypotheses, which are not independently testable,” and “specific (factual) assumptions, which are supposed to correspond to observed facts or conditions.” The former was found in Keynes’s General Theory, and the latter in his Treatise on Money, Machlup explained. He thus proposed that empirical analysis be classified independently, under two categories: “Quantitative Research Techniques” and “Social Accounting, Measurements, and Numerical Hypotheses” (e.g., census data, expenditure surveys, input-output matrices, etc.). On the contrary, Haley wanted every category to cover the theoretical and empirical work related to a given subject matter. In his view, separating them was impossible, even meaningless: “Is there any theory that is not abstract? And, for that matter, is there any economic theory worth its salt that is not applied,” he teased Machlup. Also, he wanted to avoid the idea that “class 1 is theory, the rest are applied … How about monetary theory, international trade theory, business cycle theory?” He accordingly designed the top category to encompass price theory, but also statistical demand analysis, as well as “both theoretical and empirical studies of, e.g., the consumption function [and] economic growth models of the Harrod-Domar variety,” among other subjects. He eschewed any “theory” heading, which he replaced with titles such as “Price system; National Income Analysis.” His scheme eventually prevailed, but “theory” was reinstated in the title of the contentious category.