Probabilities turn out to be surprisingly meaningless sometimes. Especially for rare unrepeatable events. A good way to make them a bit more concrete to put so

Probabilities turn out to be surprisingly meaningless sometimes. Especially for rare unrepeatable events. A good way to make them a bit more concrete to put some money on it, but even then it's hard to be sure. You can however use this to measure how good someone is in predicting. Take sports for example, by betting according to someone's prediction you can see how much money you earn (if their probabilities are 'true' you are almost guaranteed to earn money, eventually). But really in that case you're hoping that someone's ability to predict one sports match is indicative of their ability to predict the next, which is a good bet, but obviously doesn't hold for these kinds of miscellaneous rare events. In this case you can imagine a betting system, and you can imagine some people might turn out to be better at it than others (though the relevant measure is not the one used in this article), so I suppose you can talk about someone's ability to predict these events. Though in the end the bookie always wins, so make of that what you will. Of course this being probability theory all of these methods only work with high probability, so they may not work at all.