I didn't say it did. I said that P(Heads | Monday) = P(Tails | Monday) = 1/2, because it's determined by a fair coin flip that's yet to happen. This is in contrast to the standard halfer position, where P(Heads | Monday) > 1/2, and P(Tails | Monday) < 1/2. Everyone agrees that P(Heads | Monday) + P(Tails | Monday) = 1.
Or are you disagreeing with the calculation?
P(Heads) = P(Monday) P(Heads | Monday) + P(Tuesday) P(Heads | Tuesday) is just Baye's theorem.
P(Heads | Tuesday) = 0, because if Beauty is awake on Tuesday then the coin must have landed tails.
P(Heads | Monday) = 1/2 by the initial reasoning.
Then P(Monday) = 2 * P(Heads) by a teeny amount of algebra.
The probability is 1/3 per awakening and 1/2 per experiment.
Per-experiment:
Per-awakening:
I don't see anything in either of those links claiming that P(Heads | Monday) > 1/2. I assume that your reasoning to get that is something like "P(Heads | Tuesday) is less than P(Heads), so it follows that P(Heads | Monday) is greater ...
If it's worth saying, but not worth its own post, then it goes here.
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