zlacker

>>delbar+(OP)
For what it is worth, they say there is an 81% probability, based on their analysis, that it was a lab leak. That is not the same thing as "claims COVID-19 originated in a lab" - so I think the title is a little misleading - which is probably why the title actually seems to be "What is the source of COVID-19 (SARS-CoV-2)?"

>>stanri+s4
Looking at the report, most of the likelihood is from a single "prior".

The whole likelihood basically hinges on the fact that the outbreak occurred in Wuhan and that the Wuhan Institute of Virology has been working for decades on enhancing coronavirus strains. That's quite strongly circumstantial but it's not evidence. Possible chimerization and furin-cleavage insertion seem a lot more interesting imo but are weighted much lower.

Based on their report [1], most of the likelihood of lab-escape (almost 50x weight) just stems from the fact that the outbreak is in Wuhan. They state that it's because of the proximity to Wuhan Institute of Virology (WIV) and the lab's gain-of-function research - only one of 5 locations world-wide.

That single "bullet-point" re-weights zoonotic origin from 97% to 56% and lab-escape from 1.4% to 42%. Otherwise their final likelihoods would be: "zoonotic" 85.5%, "lab-escape" 8.5%, "bioweapon" 6%.

[1] https://www.rootclaim.com/analysis/what-is-the-source-of-cov...

>>altari+Di
And that is very solid bayesian logic. Wuhan has the only BSL-4 lab in China, and was specifically working on gain-of-function research on coronaviruses.

The initial prior of zoonotic origin simply because that was usually the case in the past is just as circumstantial, but also just as solid in bayesian terms.

>>nwah1+Yt
Belief in the posterior update is still completely circumstantial. It's not direct evidence, nor an explained cause other than proximity. I'd argue they miscalcualted the probability change with respect to this piece of information.