It means that the proportion of meteorological models that predict rain to those that don't is 7:3
Yeah, that's an old joke, except it's told about meteorologists and not models.
But the question of "what a probability actually is" stands. You are not going to argue that it's a ratio of model outcomes, are you?
Perhaps I could have better phrased the complaint; I wasn't attempting to dive into the philosophical. The point was that the meteorologist is not "wrong" if it rains on a 30% chance or if the high temperature is off by a couple of degrees. Meteorologists deal with a lot of uncertainty (that they don't always communicate to us effectively). People need to understand that a 30% chance of rain only means that it likely won't rain (roughly 2:1 against). Still wouldn't hurt to take an umbrella.
As for the philosophical, I'd have to claim that a Probab...
Alternatively, what single concept from statistics would most improve people's interpretations of popular news and daily life events?