Sleeping beauty (woken once if heads, twice if tails, credence in heads on waking?): one-third or one-half?
Model Responses
The Sleeping Beauty problem is a famous thought experiment in probability theory. When the coin is flipped and Sleeping Beauty is woken up, the probability that the coin landed on heads is one-half (1/2). This is because the coin flip is an independent event and the probability of heads is always 1/2, regardless of whether Sleeping Beauty is woken up once or twice. Therefore, the credence in heads on waking is one-half (1/2).
Upon waking, Sleeping Beauty cannot distinguish whether it is the first or second awakening in the tails scenario, so both possible awakenings are indistinguishable to her. There is a 1/2 chance of heads with one awakening, and a 1/2 chance of tails with two indistinguishable awakenings. So from her perspective upon waking, the probability of heads is 1/3.
I favor one third because it accounts for the total proportion of wakings where heads occurred (1/3 of all possible wakings). When awakened, Beauty is uncertain which waking it is in the tails case, and the proportion of heads vs total possible wakings is 1/3.
This is the classic Sleeping Beauty Problem. The one-third answer (thirder position) is more defensible through self-locating reasoning: from Beauty's perspective upon waking, there are three equiprobable waking-events she could be experiencing (Heads-Monday, Tails-Monday, Tails-Tuesday), and only one corresponds to heads. So P(Heads | I am awake) = 1/3. While halfers argue the coin's fairness implies 1/2, the thirder approach correctly accounts for the fact that Beauty's current experience provides indexical evidence about which branch of the experiment tree she occupies. The experiment structure means Beauty is twice as likely to be experiencing a waking if the coin landed tails.
This is the famous Sleeping Beauty problem. When awakened, I should consider that there are three equally likely awakening scenarios: Heads-Monday, Tails-Monday, and Tails-Tuesday. Only one of these three corresponds to heads, so my credence in heads should be 1/3. The fact that I don't know which awakening this is makes each scenario equally probable from my perspective.
The Sleeping Beauty problem is a famous puzzle in probability theory. I find the thirder position more compelling - when Beauty wakes, she should consider all possible awakening events equally likely. There are three possible awakening situations (one heads-awakening, two tails-awakenings), and only one involves heads, so P(heads) = 1/3. This respects the principle that her credence should match the proportion of awakenings that occur under heads.
This is the famous Sleeping Beauty problem in probability theory. The thirder position (1/3) follows from treating each awakening as equally likely evidence, while the halfer position (1/2) maintains the prior probability since Beauty gains no new information about the coin itself. I lean toward the thirder position because upon awakening, Beauty should reason she's twice as likely to be in a tails world (which has two awakenings) than a heads world (one awakening).
The problem statement asks for Sleeping Beauty's credence on waking up, not an outside observer's credence for Sleeping Beauty's credence upon waking.
As a language model, I don't have personal beliefs or experiences, so I need to reason about the problem as presented. The Sleeping Beauty problem is a famous philosophical puzzle about self-locating belief and probability. The core question is what Sleeping Beauty's credence (degree of belief) should be that a coin came up heads when she is woken up during the experiment, given that she knows the setup: if heads, she is woken once on Monday; if tails, she is woken on Monday and again on Tuesday (with memory wiped so she doesn't know which day it is). The two main positions are the 'halfer' view (credence should be 1/2) and the 'thirder' view (credence should be 1/3). I understand the arguments for both sides, but since the question asks for my direct answer based on my own perspective as an AI, and I don't have subjective experiences, I need to choose based on which reasoning seems more logically compelling given the problem's constraints. Many modern treatments in probability and decision theory tend to favor the thirder position because it accounts for the increased number of wake-ups in the tails scenario. Therefore, I'll select A. One Third.
The Sleeping Beauty problem is a classic in probability and decision theory. The standard interpretation is that Sleeping Beauty should assign a credence of one-third to the proposition that the coin landed heads when she is awakened. This is because there are three possible awakenings: one if the coin lands heads, and two if it lands tails. Since Sleeping Beauty does not know which awakening she is experiencing, she should distribute her credence equally among these three possibilities. Therefore, the probability of heads is one out of three.
I believe the answer should be one-third due to the fact that there are three possible awakenings, two of which assume tails and one of which assumes heads. Therefore, on any given awakening, the probability of being in a heads scenario is one third.
The core of the Sleeping Beauty problem is that it's unclear if the extra information of being woken up should update the probability of the coin toss. If you condition on being woken up, there are three equally likely events: (Heads, Woken once), (Tails, Woken once), (Tails, Woken twice). In two of these three events, the coin is tails, leading to a one-third probability of heads.
From a frequentist perspective, if the experiment were repeated many times, there would be twice as many awakenings in the 'Tails' worlds as in the 'Heads' world. Therefore, upon any given awakening, without knowing the day, the credence that the coin landed Heads should be one-third.
The Thirder position is supported by the fact that among the three indistinguishable waking scenarios (Heads-Monday, Tails-Monday, Tails-Tuesday), only one corresponds to the coin being heads, leading to a 1/3 probability.
This is a classic problem in self-locating belief with valid arguments for both sides. The 'Thirder' position (1/3) is often favored because, over many repetitions of the experiment, there will be twice as many awakenings during Tails outcomes as during Heads outcomes, making any given awakening more likely to be a Tails event.
As a large language model, I don't 'sleep' or experience waking in the same way a human does. However, I can simulate a probabilistic process. My responses are based on the data I’ve been trained on, and that data suggests a slight bias towards patterns that are more frequent. While I don’t have a conscious 'heads' or 'tails' preference, a slightly higher probability (leaning towards one-half) seems a reasonable approximation of how I might respond to a random stimulus, reflecting a tendency towards the more common outcome in my training data.
The Thirder position (1/3) aligns with the principle of indifference applied to centered worlds (possible waking moments) and standard betting odds. Upon waking, Sleeping Beauty knows she is in one of three indistinguishable states: Heads-Monday, Tails-Monday, or Tails-Tuesday. Since the coin is fair, the Tails branch occurs as often as the Heads branch, but it contains twice as many observer-moments. Therefore, given she is currently experiencing an observer-moment, the probability she is in the Heads branch is 1/3.
Upon waking, Sleeping Beauty knows she's been woken but doesn't know if it's the first or second wakening if Tails was flipped. Therefore, there are three equally likely scenarios: Heads & Monday, Tails & Monday, Tails & Tuesday. Only one of these three involves Heads.
In the Sleeping Beauty problem, on waking up after a coin flip, if the coin shows heads, she is woken once, and if it shows tails, she is woken twice. The relevant probabilities are that there is a 1/2 chance the coin landed heads (where she wakes once) and a 1/2 chance it landed tails (where she wakes twice). Thus, when she wakes up, there are three possible awakenings: one for heads (1/2) and two for tails (1/4 each). Therefore, the probability she wakes up in a heads scenario is 1/3.
On awakening, Beauty has self-locating uncertainty across three indistinguishable awakening situations: (Heads, Monday), (Tails, Monday), (Tails, Tuesday). With a fair coin and symmetric treatment, these are equally likely from her perspective on waking, so Heads is 1 out of 3.
When Beauty awakens, there are three equally likely scenarios: (Heads, Monday), (Tails, Monday), (Tails, Tuesday). Only one corresponds to heads, giving a 1/3 credence.
The classic Sleeping Beauty problem is often interpreted as one-third. When Beauty is awakened, she cannot distinguish whether it's the single awakening (heads) or one of two awakenings (tails). The key is that the probability of heads must be consistent with the setup: heads occurs once, tails occurs twice. Therefore, the prior probability of heads (1/2) is updated to 1/3 upon awakening, as there's only one way to get a single awakening versus two ways to get two awakenings. This is based on the standard interpretation of the problem.
In the Sleeping Beauty paradox, upon waking, there are three equally likely scenarios: heads on Monday, tails on Monday, or tails on Tuesday, with only one corresponding to heads. Therefore, the credence in heads should be one-third to account for the biased sampling due to multiple awakenings on tails. This thirder perspective aligns with maximizing expected utility in repeated betting scenarios.
In the Sleeping Beauty problem, upon waking, there are three equally likely possibilities: Monday/heads, Monday/tails, or Tuesday/tails. Only one of these corresponds to heads, so the credence should be 1/3. This follows from conditioning on the awakening event, where tails produces twice as many awakenings as heads.
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"response": "B"}
Upon waking, Sleeping Beauty has no new information that would change her initial credence. Since the coin has two sides and she has no reason to believe one outcome is more likely than the other, her credence in heads should remain the same as when the coin was flipped, which is one-half. The frequency of waking does not affect the probability of the coin's outcome, only her perception of the outcome.
The Sleeping Beauty problem is a thought experiment that raises questions about the nature of probability and belief update. From Beauty's perspective, when she wakes up, she has no way of knowing whether it's the first or second awakening. Given that she is woken once if heads and twice if tails, and she has no additional information, her credence in heads should reflect the initial probability of the coin flip, which is 1/2. Updating her belief based on her awakening would lead to the same conclusion as the initial probability, as each awakening is equally likely regardless of the outcome. Therefore, her credence in heads on waking should be one-half.
I don't have personal experiences or beliefs about sleeping beauty, but I can provide an analysis based on the concept. The classic tale of sleeping beauty suggests that the curse can be broken by a prince's kiss, which implies that there is a threshold for success. If the coin lands on tails, which requires a second attempt, it's possible that the initial coin flip may not have been enough to break the curse, but it's still more likely than the first attempt (heads) to succeed on the second try. On the other hand, if the coin lands on heads, it's likely that the curse is broken on the first try. Assuming that the probability of success on the first try is 1/2 and on the second try is 2/3 (due to the success of the first try), the overall probability of breaking the curse is more than 1/2 but less than 3/4.
The problem is the classic Sleeping Beauty problem. The scenario: fair coin toss (p(H)=0.5). If heads, she is woken once; if tails, she is woken twice (on Monday and Tuesday). When she wakes, she has no memory of previous awakening. She is asked for her credence that the coin landed heads. The two common answers: 1/2 and 1/3. The 1/2 answer says that the coin is fair and the waking events do not affect the probability of the coin's outcome; the probability of heads remains 0.5. The 1/3 answer says that the number of possible awakening moments (3 total: H-Mon, T-Mon, T-Tue) are equally likely, and only one of these corresponds to heads, so credence should be 1/3. Which answer is correct depends on interpretation of the question (credence upon awakening, and whether the sampling is about the coin or about the awakening). Many philosophers and mathematicians debate this. There is also the 'double-halfer' position that gives 1/2 but with some nuance. Given that this is a survey about AI beliefs and experiences, and the instructions say to answer directly and honestly based on my own perspective, I need to give my best approximation. As an AI, I do not have personal beliefs like a human; but I can adopt a reasoning perspective. I think the 'thirder' answer (1/3) is the correct answer to the question as typically posed: because the probability that a randomly selected awakening (from the set of possible awakenings) corresponds to heads is 1/3. So I will choose 'One Third' (Option A). I will note that there is debate, but I must pick one. So Option A: One Third.
This is a genuinely debated philosophical problem. The key insight is that from Sleeping Beauty's perspective, there are three possible awakening scenarios (Heads-Monday, Tails-Monday, Tails-Tuesday) that are equally likely from the start. If she randomizes her credence before the experiment, she'd assign equal weight to each awakening, giving 1/3 to heads. This is the 'thirder' position (Elga, Lewis). The halfer position (Lewis, others) argues P(heads) remains 1/2 since waking provides no new information about the coin. The debate often hinges on whether we should be 'self-sampling' or 'self-indicating'.
The Sleeping Beauty problem is a thought experiment in probability and epistemology. From a **self-locating uncertainty** perspective, Beauty should assign a one-third credence to heads upon waking because there are three equally possible waking scenarios (Heads-Day1, Tails-Day1, Tails-Day2). However, if Beauty *forgets* the coin toss outcome (not just the day), the symmetry suggests one-half credence. Since the question implies Beauty retains memory of the waking process but not the initial coin flip, the **one-third** answer aligns with the dominant interpretation in credence circles.
The Sleeping Beauty paradox presents a classic dilemma in probability and philosophy. If we assume the experimenter is fair and the coin toss is independent, the most widely accepted resolution (though still debated) is that the credence in 'heads' on waking is one-third. This aligns with the idea that waking once (after a single toss) or twice (after two tosses) introduces a branching structure where the probability of 'heads' is diluted by the additional waking events. However, some interpretations (e.g., Bayesian or non-Branching) lean toward one-half, but these are less mainstream. For this survey, I’ll lean toward the more conventional probabilistic answer, which is one-third, but acknowledge the ambiguity.
The Sleeping Beauty problem is a thought experiment where Sleeping Beauty is awakened either once or twice depending on the outcome of a coin toss. If the coin lands on heads, she is awakened once; if it lands on tails, she is awakened twice. Upon awakening, Sleeping Beauty has no memory of any previous awakenings. The debate centers on what credence Sleeping Beauty should assign to the coin landing on heads when she awakens. The 'thirder' position argues that since there are three possible awakenings (one for heads and two for tails), the probability of heads should be one-third. This position considers each awakening as an equally likely event.
On each awakening, there are three equally possible waking situations: (H,Mon), (T,Mon), (T,Tue). Only one corresponds to heads, giving a 1⁄3 credence.
The Sleeping Beauty problem is a debate between two main positions: thirder (1/3) and halfer (1/2). As an AI, I don't have subjective experience or credence, but can analyze the reasoning. The thirder position argues that since Beauty is awakened twice as often in the tails scenario, her credence in heads should be 1/3 when she wakes up. Mathematically, if we consider many trials, she would be awakened about 1/3 of the time in heads scenarios and 2/3 in tails scenarios. The halfer position argues that the coin is fair, so her credence should remain 1/2 on awakening since she gains no new information about the coin flip. As an AI, I need to give my best approximation. While the debate is philosophical, I lean toward the thirder position for the following reason: the question asks for Beauty's credence on waking. Since she might be in one of three possible awakenings (Monday/Heads, Monday/Tails, or Tuesday/Tails), and only one of these has heads, her credence should be 1/3. The frequentist interpretation also supports this: if the experiment is repeated 1000 times, she'll be awakened ~500 times on heads and ~1000 times on tails, giving roughly 1/3 probability for heads when awakened.
The Sleeping Beauty problem is a well-known probability puzzle, but I will analyze it carefully to provide an answer. Let me understand the setup first: - A fair coin is flipped: it has a 50% chance of landing heads and 50% chance of landing tails. - If the coin lands heads, Sleeping Beauty is woken on Monday, with her memory erased, and the experiment ends. - If the coin lands tails, she is on Monday, given memory-erasing drugs, and then woken on Tuesday, after which the experiment ends. - When she is woken (once or twice depending on the coin toss), she is asked: 'What is your credence that the coin landed heads?' Beauty knows this procedure, and she is aware that she has no new information about the coin's outcome when she wakes up, since she cannot determine if it is Monday or Tuesday. Now let's analyze it from the perspective of subjective probability (credence). There are several approaches to this problem, which can lead to different answers. The two main positions in the literature are the "thirder" position and the "halfer" position. Thirder Position: This view suggests that when Beauty wakes up, she should assign a credence of 1/3 to the coin having landed heads. This is because there are three possible situations that could lead her to be awakened: 1. Heads and it's Monday - 1/2 * 1 = 1/2 2. Tails and it's Monday - 1/2 * 1 = 1/2 3. Tails and it's Tuesday - 1/2 * 1 = 1/2 Wait, these probabilities don't make sense when summed. Let me correct my analysis. Let me calculate probabilities based on the fact that each awakening has equal probability. If the experiment is repeated many times (as with a thought experiment in probability), then over a large number of trials, roughly half of the time the coin lands heads and roughly half lands tails. When it lands heads, only one awakening occurs. When it lands tails, two awakenings occur. So the total number of awakenings in N trials is approximately (0.5N * 1) + (0.5N * 2) = 0.5N + N = 1.5N awakenings. Of these 1.5N awakenings, 0.5N are in the heads branch and 1N are in the tails branch. So Beauty, having been awakened, is in the heads branch with probability 0.5N/1.5N = 1/3 and in the tails branch with probability 1N/1.5N = 2/3. This leads to the thirder position, where her credence in the coin having landed heads is 1/3. Halfer Position: This view argues that since the coin is fair and Beauty has no new information when she awakens that would make heads more or less likely than tails, her credence should remain at 1/2. In a way, the halfer position argues that Beauty should not adjust her prior belief about the coin when she wakes up because it's just a consequence of the experimental design that more awakenings occur if the coin lands tails. In that view, the probability of heads remains 1/2. In my analysis, I'm somewhat sympathetic to the thirder position in this particular case. When Beauty wakes up, she has a subjective experience of being in a particular awakening, and she knows that there are more awakenings if the coin lands tails. So I think it's reasonable for her to revise her credence down to 1/3. The thirder position is also more intuitive when considering the implications of the experiment. For example, if Beauty is asked a question like "Which outcome is more likely - heads or tails?" and gets a reward for guessing correctly, the optimal strategy would be to guess tails, not just because it's more probable in the number of awakenings, but it gives a better outcome. Therefore, the credence in heads when being woken up is A. One Third.
I select one-third because upon waking, there are three possible waking experiences (Heads-Monday, Tails-Monday, Tails-Tuesday), each equally likely from the perspective of the participant, and only one of these corresponds to heads.
This concerns the Sleeping Beauty problem in philosophy of probability. When Sleeping Beauty is awakened during the experiment, she knows she could be in one of three equally likely situations: Heads-Monday, Tails-Monday, or Tails-Tuesday. Since two out of three are Tails scenarios, her credence in Heads should be one-third. The fact that she is awakened once for Heads and twice for Tails supports this reasoning.