Open thread, June. 12 - June. 18, 2017

Thomas

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If it's worth saying, but not worth its own post, then it goes here.

Notes for future OT posters:

1. Please add the 'open_thread' tag.

2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)

3. Open Threads should start on Monday, and end on Sunday.

4. Unflag the two options "Notify me of new top level comments on this article" and "Make this post available under..." before submitting

"CurrentlyMonday" as you have defined it is a per-awakening probability

The halfer position assumes that the probability that is meaningful is a per-experiment probability.

To be clear, you're saying that, from a halfer position, "the probability that, when Beauty wakes up, it is currently Monday" is meaningless?

Neither of your links to the halfer position shows anyone claiming that.

Sorry, I wrote that without thinking much. I've seen that position, but it's definitely not the standard halfer position. (It seems to be entirelyuseless' position, if I'm not mistaken.)

The per-experiment probabilities you give make perfect sense to me: they're the probabilities you have before you condition on the fact that you're Beauty in an interview, and they're the probabilities from which I derived the "per-awakening" probabilities myself (three indistinguishable scenarios: HM, TM, TT, each with probability 1/2; thus they're all equally likely, though that's not the most rigorous reasoning).

I'm confused why anyone would want not to condition on the fact that Beauty is awake when the problem states that she's interviewed each time she wakes up. If instead, on Heads you let Beauty live and on Tails you kill her, then no one would have trouble saying that Beauty should say P(Heads) = 1 in an interview. Why is this different?

Thanks again for the discussion.

To be clear, you're saying that, from a halfer position, "the probability that, when Beauty wakes up, it is currently Monday" is meaningless?

It's meaningless in the sense that it doesn't have a meaning that matches what you're trying to use it for. Not that it literally has no meaning.

I'm confused why anyone would want not to condition on the fact that Beauty is awake when the problem states that she's interviewed each time she wakes up.

It depends on what you're trying to measure.

If you're trying to measure what percentage of experiments ... (read more)

0entirelyuseless9y

This is a SIA idea, and it's wrong. There's nothing to condition on because there's no new information, just as there's no new information when you find that you exist. You can never find yourself in a position where you don't exist or where you're not awake (assuming awake here is the same as being conscious.)