The Physics of Wall Street

That is the title of a book by James Owen Weatherall. I received a review copy. I will say that I finished it, which is more than can be said for most books that I get sent to review. So I feel entitled to blog about it. The book offers short biographies of students of physics who applied their models in finance, along with layman-friendly explanations of the theories involved. A main theme of the book is that economists are too snotty toward physicists. For exaple, on p. 146-147 he describes attempts by the Santa Fe Institute to bring physicists and economists together in the late 1980s. This worked out poorly, but when the institute invited practitioners from Wall Street, “The traders proved much less defensive than the economists.”

I think that the complaint about snotty economists is pretty widespread. Experts in many disciplines, including psychology, sociology, and biology, believe that they bring techniques that would be useful to economists but are under-appreciated. I am not sure how to react. I think that what Weatherall calls the sociology of the economics profession is as bad as he says it is. But I am not part of the mainstream myself. If you ask folks in the leading departments about the state of economics, they will tell you that it is basically fine.

The book itself contains some well-written stories, a bit reminiscent of The Money Game, which most of you are too young to remember (Weatherall probably never heard of it). I learned little new from the early chapters, but I got a bit more insight into the Santa Fe Institute folks and the chapter on Didier Sornette and his models for sensing major changes was entirely new to me. After that, the book sort of petered out for me. At the end, he calls for a sort of “Manhattan Project” to apply physics to economics. Calling for a “Manhattan Project” on anything is a surefire way to put me off.

2 thoughts on “The Physics of Wall Street

  1. I think economists are indeed snotty toward other scientists who suggest importing their tools into economics, but to be fair, this is partly because other scientists typically make no effort to read and understand economics. They identify a research question and data, propose a biological or physical model, and interpret the results using their own lens, paying no attention to what has already been written on the subject by economists.

    In contrast, several economists have adapted tools from natural sciences (or other social sciences) and successfully published (Akerlof, Thaler, Kirman, Hirshman(?), Gabaix, and many others).

    So I think it is not hostility to the tools and knowledge of other fields, but the attitude that other scientists bring with them when they study economic questions.

    • Sorry — I forgot to add that the method of publishing research is very different in the natural and physical sciences. I liken it to how you slice a pizza (borrowing from M&M). In STEM fields, research is sliced finely and published in large numbers of small papers (cut a pizza into 128 slices, say), while economics and some other social sciences publish work as fewer, larger pieces. Physics journals accept 90% of submissions (even 75% in the best ones, according to their own data) and articles are very short and huge in number. That is not to say one system is better or worse, they are just fundamentally different. For example, most econophysics articles would not pass muster in good economics journals, simply because they are too ”slight” and incomplete. The diffusion of research is just done differently.