I hear a lot of people complaining about the Covid-19 modeling.
“How could they get the number of deaths so wrong,” is the common complaint. “They wrecked the economy for no good reason,” is probably the second gripe.
I say to them, the death model is based on two important criteria. One is the model is only as good as the assumptions put into the model. And two is, what outcome do you want from the model?
If going into the development of the model you wanted to shut down the economy because your assumption was that was the best way to stop the spread of the disease, then you would err on the side of far more deaths and hospitalizations.
Remember if the modeler was able to predict the future, then he or she would be making a lot more money on Wall Street than banging on a spreadsheet in some medical research lab.
Look at New York State Governor Andrew Cuomo chastised the citizens for not self-isolating by citing a model that said 130,000 hospital beds would be needed and that he only had 35,000 at the time. He used the model to successfully keep New Yorkers sheltering in place.
So while the government leaders may or may not know that modeling is really based on a preconceived premise before you even create the spreadsheet and graphs, it appears they used the tool to get the desired results.
One other point, for those who say isolation and social distancing reduced the number of deaths and hospitalizations, I refer you back to my point about being able to predict the future. The models in no way could have predicted how compliant the general public would be in adhering to the request to shelter in space.
So when people and pundits lambast the CDC for incorrect modeling, they don’t realize the basic premise, which has more to do with social engineering than predictive math.