Thread. It looks like the IHME model is fond of drawing curves that are quite symmetric, i.e. they expect deaths to fall about as fast as they expect them to rise. There& #39;s no particular reason to expect this, empirically or theoretically, however. https://twitter.com/CT_Bergstrom/status/1250374214822973441">https://twitter.com/CT_Bergst...

Instead, we& #39;re seeing signs of asymmetry. In New York, things do look like they& #39;re getting noticeably better, but they& #39;re not getting better as quickly as they& #39;re got worse. Same in Italy; there& #39;s a decline in deaths, but it& #39;s not particularly symmetric. Spain is more ambiguous.

Indeed asymmetry is what you might expect given best guesses about how well social distancing works. Here are curves from Imperial College, for instance, which imagine turning social on & off. Note that they& #39;re somewhat asymmetric; cases don& #39;t decline quite as fast as they rose.

FWIW, the White House& #39;s model—if this is actually a representation of it, this is from their press briefing—*also* seemed to assume a lot of symmetry. I& #39;m worried that models that imply symmetry will overestimate how fast deaths will fall, even if they get the peak about right.