The Sleeping Beauty Problem: Any halfers here?

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Discussion Overview

The discussion centers around the Sleeping Beauty problem in probability theory, specifically debating the correct probability of the coin toss outcome when Sleeping Beauty is awakened. Participants explore the implications of different interpretations of the problem, including the arguments for both the "halfer" perspective (1/2) and the "thirder" perspective (1/3). The scope includes theoretical reasoning and conceptual clarification.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Mathematical reasoning

Main Points Raised

  • Some participants argue that the correct answer is 1/3, suggesting that the probability should account for the number of times Sleeping Beauty is awakened based on the coin toss outcome.
  • Others contend that the probability remains 1/2, asserting that Sleeping Beauty learns nothing new when she is awakened, thus her a priori probability should not change.
  • A participant presents a personal anecdote to support the 1/3 argument, claiming that their experience of waking up leads them to assume a specific time range, despite equal probabilities.
  • Some participants challenge the idea that additional awakenings (e.g., waking her multiple times) change the probabilities, arguing that her knowledge remains unchanged regardless of the number of awakenings.
  • One participant introduces a hypothetical scenario involving execution based on guessing, suggesting that this could influence the probabilities and biases in decision-making.
  • Another participant proposes a variation of the problem where Sleeping Beauty is only awakened under certain conditions, questioning how this affects the probability assessment.
  • Several participants engage in back-and-forth questioning about the implications of knowledge and information gained during the experiment, with no clear resolution on whether this affects the probability outcomes.

Areas of Agreement / Disagreement

Participants do not reach a consensus, with ongoing disagreement between those supporting the halfer perspective (1/2) and those advocating for the thirder perspective (1/3). The discussion remains unresolved, with multiple competing views presented.

Contextual Notes

Participants express uncertainty regarding the impact of additional information and the nature of the awakening process on the probabilities. There are also references to the differences between this problem and other probability puzzles, such as the three doors riddle, which remain unresolved.

What is Sleeping Beauty's credence now for the proposition that the coin landed heads?

  • 1/3

    Votes: 12 33.3%
  • 1/2

    Votes: 11 30.6%
  • It depends on the precise formulation of the problem

    Votes: 13 36.1%

  • Total voters
    36
  • #601
Ken G said:
I am not making up my own, that is precisely the definition I am using.

The definition you are using is in ordinary language, and as I've already pointed out several times in this thread (though a while ago now), ordinary language is vague. That is what you and @Stephen Tashi are illustrating. As soon as you both agree on the actual mathematical problem being posed, you agree on the answer. So the only dispute left is about vague ordinary language. Such disputes are pointless IMO.
 
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  • #602
Thread closed for moderation.

Edit (Dale): after discussion, the thread will remain closed
 
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