Although I have not followed the debate and certainly I did not remember the impact of the paper, I can tell that this type of analysis is quite common in mainstream economic journals. There are many papers pointing out at the relationship between diversity (e.g., ethnic) and development or social cohesion.

Thank you for your answer. It gives a case of evidence that economists were not specially impressed by Ashraf and Galor's paper.

You are right to point it that there are many papers that only see correlations but make few reflections of how the causality works between so long a chain between genetic diversity and the state of economic development.

Dear Yoshinori,

It is a waste of time to read such stupid articles. Your question brought me to look it through (a ten minutes “diagonally reading”. A look on most of the “Figures” shows that the authors are not good in statistics. Even in high-level journals like the AER, one can find many articles which fall under – what I call – nonsense economics. But the problem with this article is that it is a form of racism in economics, (hidden) in genetic clothes.

Dear Yoshinori Shiozawa , thanks for your invitation to new discussion. I am stunned. "Chain between genetic diversity and the state of economic development..." No way!

I have searched Retraction Watch data base for those authors and for this article, there is no evidence that paper was rejected.

The American Economic Review has published it. It would be fine to realize who the peer reviewers are?

https://retractionwatch.com/

Dear Anton,

yes, you are right. It does not deserve wasting our time to read the paper. But, I believe this may give a good example how the "correlation only" researches are dangerous.

Ljubomir Jacić

thank you for informing about Retraction Watch. I didn't know it.

Economics needs a kind of Copernican revolution. Neoclassical economics is a kind of geocentric system. The trouble is that it is still discovering new field of applications like Asharaf and Galor (2013). In this case, the causal chain, if it ever exists, is extremely long and almost all people with common sense would notice its stupidity except those indoctrinated in neoclassical economics and its practice.

Dear Pierre Leviaux

thank you for the information.

I could download one of the two:

Leviaux and Parent 2018 The Biological Hypothesis in Cliometrics of growth: a methodological critique of Fogel (post 1982) and Ashraf & Galor (2013). Journal of Evolutionary Economics 28:929–950.

But I could not download the other:

Leviaux 2021 Is Economic Growth Biologically Driven? Some Epistemological Reflections on Recent Developments in Cliometrics of Growth. History of Economic Ideas 28(3):89-125.

Can you share the PDF with me? If possible, please send me an e-mail at

[email protected].

Although I think that neclassical economics is wrong ("Nonsense Economics"), one cannot make it responsible for such stupidities like Ashraf/Galor's paper. The newest branches of Neoclassics - New Classical and New Keynesian models - do not use statistics/econometrics, but "calibrate" the coefficients of the functions in their numerical models.

Stupid things can happen in all sciences, the astonishing is that such an article was published in AER.

Dear Anton Rainer

having read Pierre Leviaux 's paper Is Economic Growth Biologically Driven? (The second paper in his list of 3 days ago), I came to understand the "scientific"(?) circumstances on why Ashraf and Galor 2013 "The 'Out of Africa' Hypothesis" paper appeared. The authors wanted to defend themselves but fortunately it seems they have failed.

I am relieved to know this for two reasons. First, my intuition was confirmed. Second, there are still sound sciences that can refute "such stupidities".

However, the state of economics does not keep me optimistic. I came to know Ashraf and Galor (2013) when I was reading Galor's The Unified Growth Theory (2011). I am searching who is criticizing this Theory. The key paper appeared in 2000 as Galor, O. and D.N. Weil 2000 Population, Technology, and Growth: From Malthusian Stagnation to the Democratic Transition and Beyond. American Economic Review 90(4): 806-828. More than nine papers (excluding those by Galor) appeared until 2007. They included Lucas (2004) and Hansen and Prescot (2002). They extended similar ideas as Galor and Weil (2000).

In my opinion, the distance between Galor and Weil (2000) and Ashraf and Galor (2013) is not long. Galor and his collaborators do not seriously want to find what happens in economic growth. What they want is a parable that can have a superficial coincidence between their model story and a randomly chosen phenomena. I do not think that calibration changes economics better. Calibration in economics is something disastrous, because they use to many coefficients to fit the the data. New classical and New Kyenesian economists are misusing calibration which is a necessary preparation for any observation.

Dear Yoshinori, I do not think that calibration is a progress compared with statistical testing - it is rather the contrary. I only wanted to show that parts of Neoclassical economists are against using methods applied by Ashraf and Galor. By the way, their statistical competence seems highly questionable.

You mentioned Lucas: I think, his famous critique is mainly responsible for the regress in economics since. Most mainstream economists feel obliged to introduce a (nonsense) utility function in their models (articles), which is clearly a regress against "old-fastioned" demand theories. Another name is typical for theoryless "science": Prescott. At the first view, the Hocrick-Prescott-filter is an interesting invention. But, in fact, it is without any theoretical content (even less than a trend assumption). Nevertheless, it is applied in calculations of e.g. the EU Commission and professors in Economics accept papers of their students only if they apply the HP-filter and/or certain "mordern" econometric methods.

I have co-authored a paper that discusses A&G' s findings. See: V. Daniele, A. Di Ruggiero, The Roots of Global Inequality: The Role of Biogeography and Genetic Diversity, Journal of Development Studies (downloadable from ResearchGate).

See also: Ideen A. Riahi, Why Eurasia? A probe into the origins of global inequalities, Cliometrica.

Dear Vittorio Daniele

thank you for showing us the existence of your papers. I have skipped the paper: The Roots of Global Inequality: The Role of Biogeography and Genetic Diversity, Journal of Development Studies.

I am happy to know that there are more solid thesis based on more plausible researches and synthesis. I am also happy to know that your paper appeared in Journal of Development Studies.

I have only one question to you. I am a theoretical economist and more deeply concerned with Oded Galor's theory: the Unified Growth Theory (UGT).

We can say that it is a third generation of neoclassical growth theory while the first is Solow's "class ical" growth theory and the second is Romer and Lucas and their followers's "new growth theory" or "endogenous growth theory." Galor's UGT is new only in the point that it incorporates Malthusian period. My impression is that Ashraf and Galor (2011) is deeply inspired by Galor's UGT. Therefore, it is necessary to criticize the UGT in order to reject Ashraf and Galor (2011)'s thesis. What do you think of my impression?

By the way, does someone know a theory or model that examined Boserup's hypothesis?

I find the discussion above seriously misguided (and also shows lack of respect for some colleagues)

First, yes, Unified Growth Theory (UGT) can be seen as a third generation of growth model, after neo-classical growth models and endogenous growth models. Second, the "Out of Africa" approach is almost unrelated to UGT, apart from the objective of searching for deep roots of development. The "Out of Africa" paper was violently criticized by a set of anthropologists, see here,

https://dash.harvard.edu/bitstream/handle/1/32192696/669034.pdf

to whom Oded Galor and coauthors answered here:

https://economics.brown.edu/sites/g/files/dprerj726/files/papers/2018-13_paper.pdf

Caraher, R., & Ash, M. (2018). Genetic Diversity and Economic Development: Assessing the Key Findings in Ashraf and Galor (2013). UMASS Amherst Economics Working Papers.

David de la Croix

you find "the discussion above" seriously misguided. Are you talking about my post addressed to Vittorio Daniele or any other posts? Please specify it and explain why you think it is seriously misguided.

In their paper, Ashraf and Galor refer to the Unified Growth Theory implicitly by asking "the origins of the differential timing of transitions from stagnation to growth" (in Introduction), because the Unified Growth Theory is what Galor claims to explain why and how transitions from stagnation to growth occurred. It is natural enough to ask if there is some deep theoretical and methodological liaison between the UGT and the "Out of Africa hypothesis" in Ashraf and Galor's sense. I have no doubt on The Out of Africa hypothesis in anthropology itself.

Why did I find the discussion misguided? it contains many mistakes (ex: (1) Hansen Prescott has deterministic technical progress, so it does not belong to UGT, but rather to neo-classical growth models. (2) All the discussion on calibration. etc), and is sometimes rude to colleagues or disciplines (ex: Second, there are still sound sciences that can refute "such stupidities". In rainer post: Although I think that neclassical economics is wrong ("Nonsense Economics"). their statistical competence seems highly questionable - all those statements are very rude).

I support others

David,

Drawing quadratic "trends" into clouds of partly very soft (not to say weak) data - like Ashraf & Galor did in Figures 5-8 - is not serious statistics.

Anton: said like that, this is an acceptable point of view which can be debated. But no need to attack "economics" or "calibration" or the "HP-filter" or Ed. Prescott etc. to make your point.

David,

I have mentioned "calibration" only to show, that Neoclassical theory is not only derived from statistical (cor)relations (as one of Yoshiinori's answers might be understood). When building a model, calibration will often be necessary, if there is a lack of data or - to a certain extent - important for the specification of a testable model/function. But if there are data, an estimated model is by far better than one with calibrated coefficients.

I did not attack economics (which I studied, used in my profession and has always been one of my hobbies), but I simply maintain that Neoclassics is wrong. For one of its newest branches - the New Keynesian model - I think, I have proved it (see "Nonsense Economics") and it is rather easy to prove it for New Classical models.

What concerns the HP-filter, it is a theory-less (I see no science with a theoretical base for it) instrument to smooth away outlayers of a data set. I know that many econometricians are fond of it, because they get (seemingly) better statistics without need to explain these points. It is simply more comfortable. But outlayers may contain more information than "normal" data. I think, that data after HP are much less valuable than before.

Dear David de la Croix ,

thank you for responding. I have not claimed that Hasen and Prescott (2002) Malthus to Solow, American Economic Review 92(4): 1205-1217 is a kind of UGT. The word "similar" was not good, because it is too ambiguous. What I wanted to say was that Hansen and Prescott had a similar picture with Galor of the long-run development of economic history: long stagnated period to be overcome by a rapid real output growth per capita.

Here is the introductory part of Hansen and Prescott (2002):

• Prior to 1800, living standards in world economies were roughly constant over the very long run: per capita wage income, output, and consumption did not grow. Modern industrial economies, on the other hand, enjoy unprecedented and seemingly endless growth in living standards.

You may know this part. I wanted to say that this idea is quite close to that of Galor. The intention of Hansen and Prescott (2002) in writing their paper is also quite similar to that of Galor. They note in his Conclusion that

• This paper contributes to a recent literature describing unified growth models that can account for the basic growth facts of both eras, as well as the transition between the two.