Mainstream economics — an explanatory failure2 November, 2016 at 10:25 | Posted in Economics | Leave a comment
To achieve explanatory success, a theory should, minimally, satisfy two criteria: it should have determinate implications for behavior, and the implied behavior should be what we actually observe. These are necessary conditions, not sufficient ones. Rational-choice theory often fails on both counts. The theory may be indeterminate, and people may be irrational. In what was perhaps the first sustained criticism of the theory, Keynes emphasized indeterminacy, notably because of the pervasive presence of uncertainty. His criticism applied especially to cases where agents have to form expectations about the behavior of other agents or about the development of the economy in the long run. In the wake of the current economic crisis, this objection has returned to the forefront. Before the crisis, going back to the 1970s, the main objections to the theory were based on pervasive irrational behavior. Experimental psychology and behavioral economics have uncovered many mechanisms that cause people to deviate from the behavior that rational-choice theory prescribes.
Disregarding some more technical sources of indeterminacy, the most basic one is embarrassingly simple: how can one impute to the social agents the capacity to make the calculations that occupy many pages of mathematical appendixes in the leading journals of economics and political science and that can be acquired only through years of professional training? …
I believe that much work in economics and political science that is inspired by rational-choice theory is devoid of any explanatory, aesthetic or mathematical interest, which means that it has no value at all. I cannot make a quantitative assessment of the proportion of work in leading journals that fall in this category, but I am confident that it represents waste on a staggering scale.