Have you ever wondered why there are so many prophets of doom? Because it pays to anticipate calamity. In the public, forecast evaluation often only takes place once an extreme event has been observed, in particular, if forecasters have failed to predict an event with high economic or societal impact⁽¹⁾.

In a nutshell, if forecast evaluation proceeds conditionally on a catastrophic event having been observed, always predicting calamity becomes a worthwhile strategy. Given that media attention tends to focus on extreme events, skillful forecasts are bound to fail in the public eye, and it becomes tempting to base decision-making on misguided inferential procedures. We refer to this critical issue as the forecaster’s dilemma.

Oh, don’t ask me who will win the French election today!

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(1) Lerch, Sebastian, Thordis L Thorarinsdottir, Francesco Ravazzolo, Tilmann Gneiting, and others. 2017. ‘Forecaster’s Dilemma: Extreme Events and Forecast Evaluation’. Statistical Science 32 (1): 106–127.