I've found that I have benefitted from "making up" probabilities in some circumstances. I have an unfortunate but probably normal tendency to think something along the lines of, "Just as I would have predicted," whenever something happens which confirms my general attitude about that thing. Of course, I don't notice when the converse happens, and it doesn't occur to me to be surprised, and thus I don't update. Standard Confirmations Bias really.
But if I explicitly think, "There's a 70% chance Bob will be late to our meeting," and then Bob is early, I've provided myself with the useful and inescapable information that I may be miscalibrated about Bob's punctuality and may be selectively remembering one time his lateness cost me something. If I never tried to make an internalized probability assessment, I would not have been surprised in the same way. This is probably because I would cover up my mistaken nonverbal expectation of Bob's lateness with some other fallacious thought like, "Well, nobody is late all the time."
Today's post, When (Not) To Use Probabilities was originally published on 23 July 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
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