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Forum » Math/Philsophy bros GTFIH for a simple problem that will blow your mind
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Thread: Math/Philsophy bros GTFIH for a simple problem that will blow your mind

post 1522903361 10-17-2017, 10:34 AM
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#91
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u guys need to realize that being woken up at all and knowing the experiment does add some new information...there are 2 ways she wakes up with tails and 1 way she wakes up with heads, all with equal probability. That's why it's 1/3. It's also 2/3 that it is a Monday if you ask her what day of the week she thinks it is.
post 1522904431 10-17-2017, 10:42 AM
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Originally Posted By wincel⏩
u guys need to realize that being woken up at all and knowing the experiment does add somenewinformation...there are 2 ways she wakes up with tails and 1 way she wakes up with heads, all with equal probability. That's why it's 1/3. It's also 2/3 that it is a Monday if you ask her what day of the week she thinks it is.
This is where the misunderstanding is, I think. All the information you are saying is not new. She could figure out all of this before the experiment....before being put to sleep initially. How does the simple act of waking up contribute anything at all, new-wise? There is nothing remarkable about the fact, it was 100% certain she would wake up, at least once.

I don't see any clear arguments against 1/2. I admit, I'm having an easier time supporting 1/2, than I am of rejecting 1/3 (which really should be considered two different tasks).
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post 1522910571 10-17-2017, 11:31 AM
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#93
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Originally Posted By mulletwarrior⏩
I am loling because I am imagining the time that you put into making this garbally gook nonsense. But in the end you just pull apetitio principiiand say "each of these factors I made up must be 1/3 because I made up three factors."

lol, just lol at you.

And lol at anyone else that still thinks it is 1/3.
They are 1/3 because they have equal probability and add up to 1. The quoted poster asked for an explanation for 1/3rd so I gave it.
It's more like just lol at you for taking some sort of intellectual superiority in the matter. Questions like this with different interpretations are everywhere and are simply not well defined questions which can't have math applied to them. Play in traffic.
post 1522911841 10-17-2017, 11:40 AM
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Originally Posted By skunkshark⏩
They are 1/3 because they have equal probability and add up to 1. The quoted poster asked for an explanation for 1/3rd so I gave it.
It's more like just lol at you for taking some sort of intellectual superiority in the matter. Questions like this with different interpretations are everywhere and are simply not well defined questions which can't have math applied to them. Play in traffic.
Hence, the question begging.
mo e
post 1522912081 10-17-2017, 11:41 AM
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Originally Posted By numberguy12⏩
This is where the misunderstanding is, I think. All the information you are saying is not NEW. She could figure out all of this before the experiment....before being put to sleep initially. How does the simple act of waking up contribute anything at all, new-wise? There is nothing remarkable about the fact, it was 100% certain she would wake up, at least once.

I don't see any clear arguments against 1/2. I admit, I'm having an easier time supporting 1/2, than I am of rejecting 1/3 (which really should be considered two different tasks).
it is new because it gives additional information about what has happened i.e. that is isn't both tuesday and the coin was heads because then she wouldn't be awake. to start there were 4 possible outcomes: awake monday heads, awake monday tails, awake tuesday tails, asleep tuesday heads...being awake eliminates one of the 4.
post 1522913831 10-17-2017, 11:54 AM
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Originally Posted By iceypain⏩
it is new because it gives additional information about what has happened i.e. that is isn't both tuesday and the coin was heads because then she wouldn't be awake. to start there were 4 possible outcomes: awake monday heads, awake monday tails, awake tuesday tails, asleep tuesday heads...being awake eliminates one of the 4.
Moran
post 1522914151 10-17-2017, 11:56 AM
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Originally Posted By mulletwarrior⏩
And lol at anyone else that still thinks it is 1/3. OP, I am still waiting for you to accept my challenge and show me one serious person who says it is 1/3 (hint: sending me a link to a flat earthers msg board doesn't count).
Even though you are red I will respond to your 'challenge' with this something straight from princeton/JSTOR:https://www.princeton.edu/~adame/pap.../sleeping.html

Tldr...they say it was 1/3
post 1522914261 10-17-2017, 11:57 AM
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#98
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Originally Posted By iceypain⏩
it is new because it gives additional information about what has happened i.e. that is isn't both tuesday and the coin was heads because then she wouldn't be awake. to start there were 4 possible outcomes: awake monday heads, awake monday tails, awake tuesday tails, asleep tuesday heads...being awake eliminates one of the 4.
Not sure how to explain that..."additional information that it isn't both Tuesday and the coin was heads" is not additional information at all. It is clearly known before the entire experiment.
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post 1522915021 10-17-2017, 12:03 PM
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#99
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Originally Posted By numberguy12⏩
Is it 50/50? Let's take a look at this claim. Not taking a side, rather just playing devil's advocate. The claim you are making here is: given Monday, then 50/50 chance of heads was flipped. In other words, if the experimenter tells Beauty that it is Monday, she says 50/50 chance of heads/tails. It does sound reasonable.

But consider the version of this experiment where heads means Beauty is woken up only on Monday, and tails means she is woken up a trillion days in a row, starting Monday. Now, if Beauty was awoken, and told it was Monday, would it still be 50/50 chance for heads? The analogy from the claim above you made, would say yes. (Note this modification of a trillion wake ups does not change the logic of the experiment, just the relative magnitudes of probabilities).

But in this scenario, if tails were flipped, she hit the most absolutely insane jackpot (if her waking up on each of those tails days is equally probable, then Monday being the day is 1/trillion). Would it make more sense that she concludes that heads was the more probable result of the flip? So P(H) given Monday is not 50%?
P(H) given the first monday is still 50%, I don't see how the trlliion days if tails set up changes that. In your version P(H) given she is awake would be infinitesimally small.
post 1522915581 10-17-2017, 12:08 PM
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Originally Posted By numberguy12⏩
Not sure how to explain that..."additional information that it isn't both Tuesday and the coin was heads" is not additional information at all. It is clearly known before the entire experiment.
tuesday and heads was possible at the beginning of the experiment but she would be asleep. now that she's awake, retrospectively, she knows that it's not possible that that's what happened...it's simple
post 1522916221 10-17-2017, 12:13 PM
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#101
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0.5 * 0.6667

= 0.335

(0.5 + 0.667) / 2 = 0.58335

0.58335 + 0.335 = 0.91835

0.91835 / 2 = 0.45


100% chance the coin is flipped, 100% she wakes up, 100 % the coin is heads OR tails, 45% chance it was tails
you should read this
https://forum.obnoxiousbrutes.com/showthread.php?t=179438063

negs for using "of" where it should be "have"
post 1522916291 10-17-2017, 12:13 PM
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#102
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Originally Posted By KMadigan777⏩
Even though you are red I will respond to your 'challenge' with this something straight from princeton/JSTOR:https://www.princeton.edu/~adame/pap.../sleeping.html

Tldr...they say it was 1/3
I will check it out when I get time. I have been looking into this as well, and found a very interesting, and clever argument that supports 1/2, and rejects 1/3. Particularly note the last section about the generalized sleeping beauty problem. It requires just a small bit of mathematics and knowledge of conditional probabilities:

http://web.mit.edu/rog/www/papers/sleeping_beauty.pdf

In summary, the author is constructing a situation where Beauty awakeneddoesgive us new information, by making the waking process depend on a probability machine doing the waking, with a set probability c that it works, in the range c€(0,1]. The case c=1 would correspond to our simplistic sleeping beauty problem here. And he shows in this case, P(H) = 1/2 makes more sense.
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post 1522916651 10-17-2017, 12:16 PM
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#103
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Originally Posted By KMadigan777⏩
Even though you are red I will respond to your 'challenge' with this something straight from princeton/JSTOR:https://www.princeton.edu/~adame/pap.../sleeping.html

Tldr...they say it was 1/3
Thank you.

It appears that the work is highly criticized. But, although this paper suggests otherwise, the author is clearly very clever as he has attained a position as a charlatan, er, professor of philosophy at Princeton. Props to him for being able to ride that cushy academia wave.
mo e
post 1522916881 10-17-2017, 12:18 PM
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#104
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Originally Posted By iceypain⏩
tuesday and heads was possible at the beginning of the experiment but she would be asleep. now that she's awake, retrospectively, she knows that it's not possible that that's what happened...it's simple
You are Beauty and going into this experiment. Before you are put to sleep in the first place. You are told:

-If heads, you are woken up just on Monday.
-If tails, you are woken up both Monday and Tuesday.

You can clearly conclude that you will never be woken up Tuesday w/heads. This is simply logical deduction. Before the experiment even takes place.
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post 1522917451 10-17-2017, 12:22 PM
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#105
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Originally Posted By numberguy12⏩
You are Beauty and going into this experiment. Before you are put to sleep in the first place. You are told:

-If heads, you are woken up just on Monday.
-If tails, you are woken up both Monday and Tuesday.

You can clearly conclude that you will never be woken up Tuesday w/heads. This is simply logical deduction. Before the experiment even takes place.
You sound confused. You can conclude that you will never be woken on tuesday with heads, which is why being woken gives you new information (that it is not tuesday with heads).

Simply being told that you wont be woken on tuesday if it's heads doesn't mean tuesday will not come if the coin does indeed flip heads---you just won't be awake to be asked the question.
post 1522918701 10-17-2017, 12:34 PM
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The 1/2 guys, riddle me this, imagine its the same thing but if its tails, you will be woke up 1000 times over the next 2 days, asked a question, put to sleep. Only once for heads.
If you wake up any single time, what are the odds its the ONE time because it was heads, or the thousands of times because it was tails?
post 1522921171 10-17-2017, 12:52 PM
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#107
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Originally Posted By iceypain⏩
You sound confused. You can conclude that you will never be woken on tuesday with heads, which is why being woken gives you new information (that it is not tuesday with heads).

Simply being told that you wont be woken on tuesday if it's heads doesn't mean tuesday will not come if the coin does indeed flip heads---you just won't be awake to be asked the question.
I'm not sure what you are thinking is confusing. If anything, the bolded part above does not make sense.

If she knew before the experiment that it could not be tues w/heads after waking up, and then she actually wakes up and knows it's not tues w/heads, that's NEW info? lol the very fact she even would know this when waking up, is because it was known info before the experiment.
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post 1522922551 10-17-2017, 01:02 PM
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#108
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Originally Posted By numberguy12⏩
I'm not sure what you are thinking is confusing. If anything, the bolded part above does not make sense.

If she knew before the experiment that it could not be tues w/heads after waking up, and then she actually wakes up and knows it's not tues w/heads, that's NEW info? lol the very fact she even would know this when waking up, is because it was known info before the experiment.
i give up
post 1522923191 10-17-2017, 01:06 PM
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#109
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If the process was repeated 100 times, yielding 50 tails and 50 heads since it is a fair coin, she will have been woken up 100 times because the coin came up tails and 50 times because it was heads. Since she has no memory of previous wakings, the particular time at which she is woken up is equally likely to be any of these...

Which is pretty much the definition of probability: how many times an experiment gives a certain result if it is repeated enough times.
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post 1522923911 10-17-2017, 01:10 PM
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Originally Posted By KMadigan777⏩
The 1/2 guys, riddle me this, imagine its the same thing but if its tails, you will be woke up 1000 times over the next 2 days, asked a question, put to sleep. Only once for heads.
If you wake up any single time, what are the odds its the ONE time because it was heads, or the thousands of times because it was tails?
If you are sleeping beauty, there is a 50% chance you are being woken up 1 time, and a 50% chance time you are being woken up 1k times.
mo e
post 1522925671 10-17-2017, 01:23 PM
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There is 0 coin flip for the third or second day so there's no variability on any other day than the original. I hope there isn't a real debate over this braindead question. Anyone expressing 1/3 as a legitimate answer may have to re learn English

Also expanding the problem over 100's of coin flips isn't a legitimate representation of the question. There is only one flip occurring and the result is either one interview or two, it's really just algebra 1


Edit: it seems a lot of you are falling for the distraction technique in the question itself. Regardless of how many days she wakes up and is asked there is only one flip, only one variable that leads to the interviews. The results (which days she's woken up) have 0 effect on the original 50/50 chance of a single coin flip. They aren't flipping every day, just once
Hm.

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post 1522926521 10-17-2017, 01:31 PM
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#112
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Just lol at everyone saying 1/3

When she wakes up THERE IS NO NEW INFORMATION. SHE ALREADY KNEW SHE WAS GOING TO WAKE UP

And just lol at "there's 3 possibilities so they're automatically the same probability". Just no. It's 50% heads, and 50% tails. Then 25% tails monday and 25% tails tuesday
post 1522929511 10-17-2017, 01:57 PM
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Originally Posted By Slacker23⏩
If the process was repeated 100 times, yielding 50 tails and 50 heads since it is a fair coin, she will have been woken up 100 times because the coin came up tails and 50 times because it was heads. Since she has no memory of previous wakings, the particular time at which she is woken up is equally likely to be any of these...

Which is pretty much the definition of probability: how many times an experiment gives a certain result if it is repeated enough times.
I think this is a good point to be discussing the definition of probability, as it is, I believe, fundamental to the problem.

I see the argument here, and as stated before, am having more difficult time dismissing the 1/3 position as opposed to supporting the 1/2 position. One question of further inquiry is just to clarify a little more how the above bolded is being concluded.

Also wondering if anyone can spot any error or refute the argument I linked in post 102 that is pro-1/2
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post 1522959411 10-17-2017, 07:02 PM
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Originally Posted By Slacker23⏩
If the process was repeated 100 times, yielding 50 tails and 50 heads since it is a fair coin, she will have been woken up 100 times because the coin came up tails and 50 times because it was heads. Since she has no memory of previous wakings, the particular time at which she is woken up is equally likely to be any of these...

Which is pretty much the definition of probability: how many times an experiment gives a certain result if it is repeated enough times.
I can't believe you concluded 1/2 despite everything you said. 100 tails wake ups, 50 head wake ups. 1/3 it was heads, 2/3 tails.
post 1522966551 10-17-2017, 08:12 PM
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Originally Posted By numberguy12⏩
I think this is a good point to be discussing the definition of probability, as it is, I believe, fundamental to the problem.

I see the argument here, and as stated before, am having more difficult time dismissing the 1/3 position as opposed to supporting the 1/2 position. One question of further inquiry is just to clarify a little more how the above bolded is being concluded.

Also wondering if anyone can spot any error or refute the argument I linked in post 102 that is pro-1/2
almost the whole paper is spent laying out the corrrect arguments for 1/3 then he goes on to refute it using a formula where he starts with assuming P(H)P(W|H) = 1/2. obviously that circular logic will get you to 1/2.. the problem is the variable W he is using is "beauty is awake at least once" but what we are trying to find out is the event "beauty is awake right now".

do you agree that being woken gives you information about whether it is more likely to be monday or tuesday?
post 1522967881 10-17-2017, 08:25 PM
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Favourable outcomes/ possible outcomes = probability

So if there's 1 favourable outcome and 3 possible outcomes it's 1/3
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post 1522968881 10-17-2017, 08:34 PM
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Originally Posted By BetaThanU⏩
Favourable outcomes/ possible outcomes = probability

So if there's 1 favourable outcome and 3 possible outcomes it's 1/3
I don't understand how this can be possible when there is only two possible outcomes , heads or tails. The question is what are the odds of it being heads. How does the amount of days that are a result of the variable effect the problem itself? Is this a troll thread and I'm not aware or are y'all srs?
Hm.

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Bringer of the trigger
post 1522971961 10-17-2017, 09:06 PM
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#118
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Originally Posted By iceypain⏩
do you agree that being woken gives you information about whether it is more likely to be monday or tuesday?
Interesting question. I have been on the 1/3 side since the beginning, but this question solidifies it, as it WOULD be more likely its monday. (Therefore the 1/3,2/3 odds)

^Dead srs Demi
post 1522972291 10-17-2017, 09:10 PM
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#119
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Originally Posted By KMadigan777⏩
Interesting question. I have been on the 1/3 side since the beginning, but this question solidifies it, as it WOULD be more likely its monday. (Therefore the 1/3,2/3 odds)

^Dead srs Demi
Can you read what I said and explain the idea behind that being wrong? The only way it can be more than 1/2 is if the question is how often will she get it right, then the odds expand municipally, otherwise it's 50/50 for any number of days because it only implies the question if she will be right, not how often will she be right
Hm.

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Bringer of the trigger
post 1522972601 10-17-2017, 09:13 PM
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#120
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Originally Posted By KMadigan777⏩
Interesting question. I have been on the 1/3 side since the beginning, but this question solidifies it, as it WOULD be more likely its monday. (Therefore the 1/3,2/3 odds)

^Dead srs Demi
You stupid fukin tradie THATS NOT THE QUESTION.

they aren't asking her what fukin day it is.

THE QUESTION IS "WHAT WAS THE ODDS OF THE COIN BEING HEADS OR TAILS"

If I said I'll flip a coin , heads you'll get $1 , tails you'll get $999999. DOES THAT CHANGE THE CHANCE OF HEADS OR TAILS YOU LABOURING SLAVECEL LUMBER HAMMERING WARRIOR SKULL?
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