What makes forecasting hard? Forecasting pandemics is harder than many people think. In my book with George Athanasopoulos, we discuss the contributing factors that make forecasts relatively accurate. We identify three major factors: how well we understand the factors that contribute to it; how much data is available; whether the forecasts can affect the thing we are trying to forecast. For example, tomorrow’s weather can be forecast relatively accurately using modern tools because we have good models of the physical atmosphere, there is tons of data, and our weather forecasts cannot possibly …