A brain teasing probability puzzle

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Ravishing

Ravishing

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Araysar_sl said:
In the original (aka 1st round) your choice is 0/100

your round 1 choice means nothing, and set of options offered to you at the beginning of 2nd round is always the same regardless of what you selected.

it is a sleight of hand, an illusion of choice.
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Your options are NOT the same in round 2.
The RESULTS of your choices may be a Goat or a Car but the Options for round 2 are still as follow:

Door #1 or Door #2
Door #1 or Door #3
Door #2 or Door #3
 
BrutulTM

BrutulTM

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Araysar, I want you to confirm what I think you're saying.

Araysar_sl said:
I believe that the world's mathematicians and statisticians have collectively come to an incorrect conclusion on this classic problem. It is being wrongly taught in college classes around the world as we speak. I also believe that I have correctly solved this problem where they all have failed, despite the fact that I am not trained in statistics at least beyond the level of the average person. I further believe that the fact that computer simulations have shown the consensus to be correct are irrelevant.
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Is this an accurate reflection of your views?
 
Siddar

Siddar

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Araysar_sl said:
In the original (aka 1st round) your choice is 0/100

your round 1 choice means nothing, and set of options offered to you at the beginning of 2nd round is always the same regardless of what you selected.

it is a sleight of hand, an illusion of choice.
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The first round had rules that impacted the second round and the right answer in both rounds was the same box. I didn't change simply because it wasn't revealed in first round. If you don't want to acept that host has a 66% chance of having the right box at end of first round then so be it but infact Host does and that knowledge overrides the 50/50 set up in second round.
 
Araysar

Loser Araysar

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Options are always the same. 2 doors. 1 has a goat. 1 has a car.

Regardless of anything done by the host or you previously, you ultimately arrive at these 2 options. The only logical conclusion is that your or host's initial options and choices never had effect at all aside from the predetermined effect to delivering you to only 2 doors. 1 Car. 1 Goat. 1 Choice. 50/50.
 
E

Eorkern

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Cool I'm mindfucked now because of Araysar. Great ! I believe all this thread is more a problem of wording than statistic.
 
Araysar

Loser Araysar

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BrutulTM_sl said:
Araysar, I want you to confirm what I think you're saying.



Is this an accurate reflection of your views?
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"Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the other doors, opens another door, say No. 3, which has a goat. He then says to you, 'Do you want to pick door No. 2?' Is it to your advantage to take the switch?"

Since she gave her answer, Ms. vos Savant estimates she has received 10,000 letters, the great majority disagreeing with her. The most vehement criticism has come from mathematicians and scientists, who have alternated between gloating at her ("You are the goat!") and lamenting the nation's innumeracy.

World's mathematicians and statisticians?

http://www.nytimes.com/1991/07/21/us...nd-answer.html
 
Chris

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http://www.bbc.co.uk/news/magazine-24045598

So what happens on our university's open days? We do a Monty Hall flash mob. The students split into hosts and contestants and pair up. While the hosts set up the game, half the contestants are asked to stick and the other half to switch.

The switchers are normally roughly twice as successful. Last time we had 60 pairs in 30 of which the contestants were always stickers and in the other 30 pairs always switchers:

Among the 30 switcher contestants, the Cadillac was won 18 times out of 30 - a strike rate of 60%
Among the 30 sticker contestants, there were 11 successes out of 30, a strike rate of about 36%

So switching proved to be nearly twice as successful in our rough and ready experiment and I breathed a sigh of relief.
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Yeah just test it, it works. It isn't a 50/50 chance because you have information from the previous event to help you.
 
Haast

Haast

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If only we had the mathematical tools to simulate such a situation. Oh wait...

rrr_img_43394.jpg


rrr_img_43395.jpg


INB4 "it's rigged", "Haast can't program for shit", "random numbers too sharp", "the apparently sentient computer is cheating", etc.
 
Araysar

Loser Araysar

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Eorkern_sl said:
Could we stop with the goat/car retarded thing please and just call them wrong/right door.
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Afraid not bro, because "right" and "wrong" are subjective terms in relation to what is being discussed. Car and goat are objective terms.
 
Ravishing

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Araysar_sl said:
Options are always the same. 2 doors. 1 has a goat. 1 has a car.

Regardless of anything done by the host or you previously, you ultimately arrive at these 2 options. The only logical conclusion is that your or host's initial options and choices never had effect at all aside from the predetermined effect to delivering you to only 2 doors. 1 Car. 1 Goat. 1 Choice. 50/50.
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There are 3 doors, 1 has been opened, 1 had a goat, 1 has a car.
You ultimately arrive at 2 options: to switch your original choice or not.
Your original choice has had an impact on round 2.



Food break, bbl.
 
Araysar

Loser Araysar

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Haast_sl said:
If only we had the mathematical tools to simulate such a situation. Oh wait...

rrr_img_43394.jpg


rrr_img_43395.jpg


INB4 "it's rigged", "Haast can't program for shit", "random numbers too sharp", "the apparently sentient computer is cheating", etc.
Click to expand...
Cool, but this was addressed like last night. The simulation assumes that the first choice somehow affects the 2nd choice. It can't and it doesn't because the 2nd choice is always the same regardless of what has been selected in first choice.
 
Haast

Haast

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Araysar_sl said:
Cool, but this was addressed like last night. The simulation assumes that the first choice somehow affects the 2nd choice. It can't and it doesn't because the 2nd choice is always the same regardless of what has been selected in first choice.
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Still <3 Aray.

And for the record, the simulation does exactly as the situation describes. It picks a random door to hide the goat in and a random contestant-selected door. If Switch is selected, it reveals a false door then switches the choice to the remaining closed door. Otherwise, it keeps the original selection.
 
Araysar

Loser Araysar

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Fawe_sl said:
There are 3 doors, 1 has been opened, 1 had a goat, 1 has a car.
You ultimately arrive at 2 options: to switch your original choice or not.
Your original choice has had an impact on round 2.



Food break, bbl.
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bro, I am like *this* close to giving up on you. You're just rehashing the same 40 posts already made by other people.

Your original choice logically cannot have had an impact on your second choice because your second choice always has the exact same options.



If you have 2 identical quarters and you get to pick one and keep it - do you truly have a choice? Would it matter which one you picked? What if someone picked it for you and gave it to you, would you be upset that you didnt get to make a decision on what to choose? This is the essence of this problem, its the illusion of choice. This is basically what happens in the 1st round because regardless of what door or quarter you pick, you arrive at the exactly same scenario in 100 out of 100 times in Round 2.

One Car Door, One Goat Door, One Choice, 50/50
 
Tuco

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Araysar makes me glad I'm in a profession where being as wrong as he is means you will fail.
 
Araysar

Loser Araysar

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Chris_sl said:
http://www.bbc.co.uk/news/magazine-24045598



Yeah just test it, it works. It isn't a 50/50 chance because you have information from the previous event to help you.
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Yeah, it helps you to arrive to a 50/50 choice. How fucking insightful.

For it to be a true 33/67 proposition, you need to have the option of being able to stop playing after 1st round. But you don't.
 
Siddar

Siddar

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Araysar_sl said:
Options are always the same. 2 doors. 1 has a goat. 1 has a car.

Regardless of anything done by the host or you previously, you ultimately arrive at these 2 options. The only logical conclusion is that your or host's initial options and choices never had effect at all aside from the predetermined effect to delivering you to only 2 doors. 1 Car. 1 Goat. 1 Choice. 50/50.
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No there were three doors two goats and one car. You had a 33% chance of picking the car and Host has a 66% chance of having the car at the end of round one. The slight of hand is that host has tricked you into thinking its a 50/50 chance in round two. Its not the 66% chance that host has the car from round one is still in play in round two even if your wish to ignore it.
 
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