Or... if you think for a second about what probabilities are supposed to mean, there is an obvious way to check if a probabilistic forecaster is accurate https:

Or... if you think for a second about what probabilities are supposed to mean, there is an obvious way to check if a probabilistic forecaster is accurate https://projects.fivethirtyeight.com/checking-our-work/ https://projects.fivethirtyeight.com/checking-our-work/