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| Thread: The Sleeping Beauty Problem |  This thread is pages long: 1 2 · «PREV |
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idontcare
Known Hero
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posted November 10, 2013 07:46 AM |
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50:50 for the simple reason, that on none of the "results"(you always wake up, get asked, sleep and leave in the very brief version) gives you an information about the day or the times you awaked.
and since a coin has 50:50 you just say that 
Being asked 2 times, without knowing, doesnt change anything
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mvassilev
Responsible
Undefeatable Hero
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posted August 20, 2015 08:07 PM |
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I've been thinking more about this problem, and I've realized that there's a case for the 1/3 answer.
Suppose this experiment is run 1000 times. How many heads-awakenings will there be? On average, 500 - it's a fair coin, and every time it lands on heads, it produces one heads-awakening. How many tails-awakenings will there be? On average, 1000, because every time the coin lands on tails, it produces two tails-awakenings. So in the end, you should expect to have ~500 heads-awakenings and ~1000 tails-awakenings. But then there are twice as many tails-awakenings as heads-awakenings, or, to put it differently, 1/3 of the awakenings are heads-caused and 2/3 of the awakenings are tails-caused. It's true that heads and tails are equally likely outcomes of the coin flip, but heads only generates one event while tails generates two, so heads only produces 1/3 of the events. If heads produces only a third of the events, you are more likely to be in a tails-awakening than in a heads-awakening, so you should answer 1/3.
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Eccentric Opinion
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OhforfSake
Promising
Legendary Hero
Initiate
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posted August 20, 2015 08:13 PM |
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You don't say.
Sadly I don't even remember this thread.
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Tsar-Ivor
Promising
Legendary Hero
Scourge of God
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posted August 20, 2015 10:31 PM |
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That means I was right all along for the wrong reasons, story of my life.
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"No laughs were had. There is only shame and sadness." Jenny
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OhforfSake
Promising
Legendary Hero
Initiate
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posted August 20, 2015 11:06 PM |
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Only until he changes his mind again.
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Corribus
Hero of Order
The Abyss Staring Back at You
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posted August 21, 2015 01:32 AM |
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mvassilev said:
I've realized that there's a case for the 1/3 answer.
Given that 1/3 is the correct answer, I would hope there'd be a case for it.
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I'm sick of following my dreams. I'm just going to ask them where they're goin', and hook up with them later. -Mitch Hedberg
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JollyJoker
Honorable
Undefeatable Hero
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posted August 21, 2015 08:14 AM |
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It's not. There are two different answers, depending on the question:
The probability of the coin toss is always 50/50 and the fact is determined by the toss of the coin, not by the asking.
The probability of getting it right when guessing the answer is 1/3 vs. 2/3.
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