United States #CoronaVirus Update:

I've found a severe error in the formulation of the IMHE COVID-19 CurveFit program ( https://ihmeuw-msca.github.io/CurveFit/methods/). The form of the Generalized Logistic function used has been over-simplified and forces the IMHE model growth curve to be symmetrical.

Because of this error in the model's formulation, it only predicts generalized growth curves that are symmetrical with central inflection points (see example below).

The 'α' term changes the slope, the 'β' term changes the time of the inflection point, and the 'p' term changes the magnitude of the change.

Here's a form of the Generalized Logistic Function that allows the growth curve to be asymmetrical using the "nu" term.