I think you mean ~1%, not ~10%. I’m not sure that the rest of what you describe is really what is meant by “base rate”. I think you’ve mixed a few concepts toge

I think you mean ~1%, not ~10%. I’m not sure that the rest of what you describe is really what is meant by “base rate”. I think you’ve mixed a few concepts together: - if you estimate the probability based on bad data, you get a bad answer. - the base rate is a very simple model for the chance something happens – count similar events and divide by the number of potential similar events. One might describe it as an early prior before considering other information - whether or not something (the eruption) happens in a year - the probability one predicts for an event when considering more information. For example with the ‘pressure building’ model of the eruption you might decrease the probability immediately after an eruption and increase if it’s been a while (and increase a lot if smoke is coming out) - sure it’s easy to be right predicting that unlikely events won’t happen. I think the claim of the OP is more that one may hope that the good prediction record transfers to the prediction of unlikely events