How to Interpret Covid-19 Predictions
Reassessing the IHME’s Model
DOI:
https://doi.org/10.5195/pom.2021.43Keywords:
modeling, philosophy of science, epidemiology, COVID-19, forecastingAbstract
The IHME Covid-19 prediction model has been one of the most influential Covid models in the United States. Early on, it received heavy criticism for understating the extent of the epidemic. I argue that this criticism was based on a misunderstanding of the model. The model was best interpreted not as attempting to forecast the actual course of the epidemic. Rather, it was attempting to make a conditional projection: telling us how the epidemic would unfold, given certain assumptions. This misunderstanding of the IHME’s model prevented the public from seeing how dire the model’s projections actually were.
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