Links 2024-04-16 - Changing One's Mind
It is good to update.
Two posts worth sharing today on the topic of experts changing their mind.
First up is Razib Khan. He explores the many areas and ways his field of human population genetics has changed in his relatively short period in it. Interesting in its own right, this has broader lessons for how all fields evolve. Generally this is good, but sometimes it is one step forward and several steps back—I believe Scott Sumner would agree regarding macroeconomics.
An excerpt:
Just find the gene and fix the disease…if only it were that simple
During the early years of the Human Genome Project, something called the common-disease common-variant hypothesis was widely promoted as our path to discover most of the causal genes for most diseases (it was to a great extent the funding justification for early human genomics in the 21st century). This model held the promise of a single test yielding a wide panoply of risks and probabilities for everyone. In 2024 we still don’t have good tests for many diseases, and risks for many conditions like type 2 diabetes or autism are the outcome of many genes across many loci. The problems here are not simple. In some cases there are so many variants that it is not necessarily easy to define all the causal effects and create a simple and powerful statistic with any individually predictive power. In other cases, the variants might be rare within the population, and therefore not in the catalog of disease-causing variants. This doesn’t mean the problem is intractable; it’s a matter of sequencing many more humans and collecting medical data on the sequenced individuals. But this looks to be at least a two-generation rather than a single generation project, as initially projected. Arguably we have all the technology in place, from cheap sequencing to powerful computational techniques, but a focused international project may need to coalesce to push research across the finish line.
Much more at the link. Also, catch a podcast version with Jonah Goldberg here.
Next up is Kevin Erdmann. He contemplates his own underappreciation for how helpful strategies aimed at addressing the “missing middle” could be.
Beyond the obvious virtue of changing his mind (i.e., updating his priors), Erdmann makes two key points succinctly.
First, we need 20 MILLION additional homes now to normalize our housing market.
Second, the greater the improvement the lesser it would be observed, which should (but won’t) alleviate NIMBY fears. As he says,
It is a prime example of a central issue in zoning reform: If you upzone one neighborhood, the broad housing market barely notices while the the neighborhood is greatly changed. If you upzone everything, the broad housing market gets fixed and each neighborhood barely notices.