The Deep Structure of Economic Growth

When I was working on growth in the 1990s, I wrote an article on economic growth for an encyclopedia of economics. (The links in this post take you to a version of this article that I updated in 2016.) My goal was to provide an accessible introduction to our understanding of growth without shying away from its deep conceptual foundations.

  • We can share discoveries with others.
  • There are incomprehensibly many discoveries yet to be found.

The economic jargon for this first point is the “nonrivalry of knowledge;” the jargon from math and computer science for the second point is “combinatorial explosion.”

I’ve been pleasantly surprised about how well this article seems to have served its dual purpose. Non-economists have said that it helped them understand why unlimited growth is possible in a world with finite resources. Professional colleagues have been intrigued by the discussion of combinatorial explosion and its interaction with nonrivalry. Specialists and non-specialists have both latched onto the concept it points to of a meta-idea: an idea about how better to discover ideas.

The updated version also makes a point that is not well understood that is captured in the picture to the right: If we treated Shenzhen as a city-state analogous to Singapore or Hong Kong, Shenzhen has the fastest rate of GDP growth ever observed. Over the 30 years from 1980 to 2010, output in Shenzen increased 1000 fold, which implies an average compound rate of growth that exceeds 20% per year.

~16 minutes

Conditional Optimism

In the summer of 2016, I discussed an important paper by Martin Stuermer and Gregor Schwerhoff at an academic meeting and wrote up a blog post that summarized the key points from my discussion. In light of decision to award a Nobel prize in economics for work on climate change and endogenous technological progress, I thought it would be helpful to go back to the issues I discussed there. In particular, I thought it might be useful to restate my stance of “conditional optimism,” a term that has resonated for many. As I wrote back then:

Complacent optimism is the feeling of a child waiting for presents. Conditional optimism is the feeling of a child who is thinking about building a treehouse. “If I get some wood and nails and persuade some other kids to help do the work, we can end up with something really cool.”

Side Note
Resource prices over time
~10 minutes

There is more to the Gender Gap than the Partisan Divide

A recent post at reaches a conclusion that is plainly false. This is no doubt an honest mistake caused by some mixture of haste, confirmation bias, and careless overstatment. There is no reason to suspect any conscious intent to mislead; no justification for ad hominem attacks on the author.

What matters are the facts. The facts here bear on profoundly important personal experiences and equally important collective decisions. It would be inexcusable to let false statements about such facts go unchallenged or to let false claims divert attention from the question that matters: “Is the gender gap on questions about sexual harassment and assault a sign that women have a better grasp on the facts?”

~7 minutes

Jupyter, Mathematica, and the Future of the Research Paper

The Atlantic has a great article on new ways to share research results. Its three parts make three points: A graphical user interface (GUI) can facilitate better technical writing. Wolfram’s proprietary notebook showcased innovative technology, but decades after its introduction, still has few users. Jupyter is a new open-source alternative that is well on the way to becoming a standard for exchanging research results. Each is spot on. I had to learn the hard way why so many kept their distance from Mathematica.

~9 minutes

My Email Quoted by the Financial Times

The Financial Times quoted accurately the following sentence from an internal email that I wrote: “Imagine a field of science in which people publish research papers with data that are obviously fabricated. …”Some readers mistakenly assumed that this sentence was supposed to convey a hidden meaning. To be clear, I am not aware of a single instance in which someone at the Bank published fabricated data, most certainly not “obviously fabricated” data.

~3 minutes