Oldie, but goodie: You're on a gameshow when...

  • Thread starter Thread starter Mike Rotch
  • 23 comments
  • 1,277 views

What would you do?

  • It doesn't matter if I change my choice. It's 50/50 either way.

    Votes: 11 26.8%

  • I'd change my choice to Door 2, definitely.

    Votes: 26 63.4%

  • I don't know.

    Votes: 4 9.8%
  • Total voters
    41
  • Poll closed .
Mike Rotch

Mike Rotch

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Ok, so this is nothing new but is still an interesting illustration of, well, you'll hopefully see ;).

Here is the theoretical situation you find youself in:

You are on a TV gameshow, where you can choose one out of three doors. You win whatever is behind the door you choose, but you can't see what is behind each door in advance.

Behind one of the doors is your dream car. If you pick one of the two remaining doors however, you win a jug of sour milk, which you have to drink there and then (because fear is not a factor for you!).

You decide to choose Door #1. The host then opens Door #3, which reveals a jug of sour milk.

The host then asks you, "do you want to keep your choice of Door #1 or would you like to change your mind and choose Door #2?...

What do you do?

Don't cheat! I am sure the answer will come up, but as a hint, 16% is the difference.(Or is it).
 
I actually built a program for that game :lol:

Better odds always choosing after they reveal the milk, if I recall correctly, due to it reducing the odds from 1 in 3 to 1 in 2. Unless I did it all wrong :lol:

EDIT: Didn't notice there was a poll. Should I CONCEAL THE INFO I POSTED?!?
 
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Mythbusters tested this also. And yes, I'd switch :sly:
 
I'm sure Famine explained this before :lol: But choosing door 2 was the best option.
 
First thing that comes to my mind is this. :lol:



From 2:40 on.

Cheers Shaun
 
Change doors. When you picked it you had a 1 in 3 change, now he has illiminated one door you have a 2 in 3 chance if you pick the other door.
 
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I've seen Derren Brown do a similar experiment with very expensive art covered in a cloth and a knife to cut through the art. 3 stands and the museum curator holding a knife. 1 painting is the real article under one of the sheets. He explains how the choice works too.
 
lbsf1
Change doors. When you picked it you had a 1 in 3 change, now he has illiminated one door you have a 1 in 2 chance if you pick the other door.
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Your probabilities, and Azuremen's, are incorrect.

:D
 
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lbsf1
I found this very good explanation of how it works here if anyone is interested.
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Good buzzkill champ 👍.
 
Mike Rotch
Good buzzkill champ 👍.
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I was doing the math from the current selection process. I'm not entirely sure why the odds increase though to more than 50%...

I blame that on it being the AM and me not having yet slept.

And it is Azuremen. One of these days I'm just going to change it to something people can spell right, I swear.
 
Ah, the Monty Hall Problem.

At the moment you make your first selection, the odds are set. You have a 1 in 3 chance of being right and a 2 in 3 chance of being wrong. The second choice is dependent, not independent, so the odds are not reset - you still have a 1 in 3 chance of having picked the right door and a 2 in 3 chance of having picked the wrong door.
 
Azuremen
And it is Azuremen.
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Sorry...
slap.gif
 
Ive read this one before, but as the others have already solved it. Not much value I can add, other than I would pick door 2 everytime.
 
Famine
Ah, the Monty Hall Problem.

At the moment you make your first selection, the odds are set. You have a 1 in 3 chance of being right and a 2 in 3 chance of being wrong. The second choice is dependent, not independent, so the odds are not reset - you still have a 1 in 3 chance of having picked the right door and a 2 in 3 chance of having picked the wrong door.
Click to expand...

But that doesn't explain...
why when you ground out a large set of samples, the odds increase. To roughly 66%, or 2 in 3 versus the expected 1 in 3. Unless I've misread what you've put in spoiler tags.
 
I'm with Cody on this one.

Switching to door 2 gives you a 2/3 chance of getting the prize vs's a 1/3 chance of staying with your original pick
 
Azuremen
But that doesn't explain...
why when you ground out a large set of samples, the odds increase. To roughly 66%, or 2 in 3 versus the expected 1 in 3. Unless I've misread what you've put in spoiler tags.
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Because:

If you think of it being 100 doors instead of 3, the door you pick has a 1/100 chance of being correct and and the other 99 doors have a 99/100 chance of holding the car. If the host opens 98 of the other doors showing milk, the last door he hasn't opened is still a 99/100 chance of being the car. Distil it back to 3 doors and 99/100 becomes 2/3.
 
I would probably stick with door #1 - I'd be less depressed if I lost while sticking to my guns than if I flipped back and forth.
 
I switched on website got a goat next time I stuck and got car. :lol:
 
Thats pretty interesting Ive never seen this before, at first I thought you had a 50/50 chance after the host picked but then I realised the host knows where the car is and will always pick the goat for you....
The video explains it pretty well 👍
 
Azuremen
Unless I've misread what you've put in spoiler tags.
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Yes you have.

The odds are set at the start. You have a 1 in 3 chance of being right and a 2 in 3 chance of being wrong.

Thus later on in the show, if you stick with your initial choice you have a 1 in 3 chance of winning (the same as your 1 in 3 chance of being right initially) but if you change to the other remaining door you have a 2 in 3 chance of winning (the same as your 2 in 3 chance of being wrong initially).
 
I say, go for it! It's probably a bedroom set, but it sure beats the sour milk.

But then you can have a better chance at the final door choices! That's what The Price is Right copied, but they called it the Showcase Showdown.

I used think being a game show host was probably the best job in the entire world, so I learned form the masters.

...and as long as I don't have to wear some demeaning costume.

I think it would be cool if I could get Wink Martindale to be the official executor of my last will and testament.
 
The link that Luke posted explained it. Had a look at the 1 in 100 doors and it clicked 👍
 
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