u/thisisbillgates The forecasted range of new deaths for the state of New York on March 28th (yesterday) is 177 with a 95% confidence interval of 177 and between 148 and 213. From available data the number of recorded COVID-19 deaths on that day was 277, which is ~2-3 times from the median to the upper bound. I don't immediately see an available posterior to determine how invalid that prediction is, but it is certainly more than 1 in 100.

The predictions for other states seem valid. The predictions for the entire US seem to be underestimated, but basically by the degree to which New York state is underestimated. Is this disagreement something that can be easily understood? Otherwise I'm not sure the predictive power of the method has been shown to be sound, as it fails to match our current worse-case state.

(I'm not an epidemiologist but I am a data scientist)