Good thread from @CT_Bergstrom on why the @IHME_UW state projections may underestimate the extent of the problem. I’d add that the model seems to assume social distancing was the main factor in China, when in fact it was that plus massive contact tracing, isolation, quarantine.https://twitter.com/CT_Bergstrom/status/1243832582350835712 …
A possible way to explain the weakness of the model: in the range of outcomes, the date of the peak seems fixed. But that's the main thing we don't know right now.