How to Interpret Covid-19 Predictions

Reassessing the IHME’s Model


  • S. Andrew Schroeder Associate Professor of Philosophy, Claremont McKenna College



modeling, philosophy of science, epidemiology, COVID-19, forecasting


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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How to Cite

Schroeder, S. A. (2021). How to Interpret Covid-19 Predictions: Reassessing the IHME’s Model. Philosophy of Medicine, 2(1).



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