The Monty Hall Game Show

['Daniel']

If you have seen this before then please dont give the answer up. Only if you work it out.



You are a contestant on the Monty Hall game show. Three closed doors are shown before you. Behind one of these doors is a car; behind the other two are goats. The contestant does not know where the car is, but Monty Hall does.
The contestant picks a door and Monty opens one of the remaining doors, one he knows doesn't hide the car. If the contestant has already chosen the correct door, Monty is equally likely to open either of the two remaining doors.
After Monty has shown a goat behind the door that he opens, the contestant is always given the option to switch doors.




Is the contestant better sticking to the original door or switching? Answer only accepted if probabilities given as you could just guess.

 

['Daniel']

bump

 

[kelox]

stick with original choice(my guess)

 

[Chiller]

:scratch:

 

[Alexandra]

Monty hall would open a door hiding a goat either way... so i think there are equal probabilities the player has choosen the right or wrong door. so basically sticking with the first door or switching would make no difference in terms of a reasonnable choice...

 

[kelox]

:scratch:

Ok, you've swayed me. I'll say choose the other door.

 

[JTHphoto]

you have a 1 in 3 chance of being right on your first guess, if he reveals a goat behind one of the doors, you can effectively start over with a 1 in 2 chance. if you stay with your original choice you are bound by your original odds of .333333333 - if you switch, your odds improve to .5 so i would say switch. am i on the right track?

 

[kelox]

you have a 1 in 3 chance of being right on your first guess, if he reveals a goat behind one of the doors, you can effectively start over with a 1 in 2 chance. if you stay with your original choice you are bound by your original odds of .333333333 - if you switch, your odds improve to .5 so i would say switch. am i on the right track?

OK, I'll stick with my first choice.

 

[JTHphoto]

it was driving me crazy so i had to look it up, i was on the right track but my statistics skills are a little rusty...

 

[kelox]

it was driving me crazy so i had to look it up, i was on the right track but my statistics skills are a little rusty...

No, you're right, I'll say pick the second door.

 

[mentos_007]

well I hated probability at school...

 

[markc]

Okay, Mr. FunSquisher again...

I've seen this around, but the logic doesn't work. When there are three doors, you have one in three chance in getting it. When there are two doors, your odds are one in two. It doesn't matter when you picked it. The outcome is still unknown, so you still have a 50/50 chance no matter which of the two remaining doors you pick.

 

[JTHphoto]

Okay, Mr. FunSquisher again...

I've seen this around, but the logic doesn't work. When there are three doors, you have one in three chance in getting it. When there are two doors, your odds are one in two. It doesn't matter when you picked it. The outcome is still unknown, so you still have a 50/50 chance no matter which of the two remaining doors you pick.

i know this is the way it seems, but the math proves it wrong, look here to actually play --> http://math.ucsd.edu/~crypto/Monty/monty.html

WARNING: this is a spoiler and will give you the explanation, make a guess before you look.

if i am ruining this thread for you daniel let me know and i will edit/erase this... but it's cruel to leave it on here all day and not tell what the answer is...

 

[markc]

Well dang... Thanks for posting that. It looks so much like one of those horrid tales that get passed around the 'Net that sound good but are wrong. Nice to see a more in-depth explanation. It would be kind of crazy to argue with Marilyn Vos Savant too.

 

[kemplefan]

i took a three week summer course on this(by choice, no realy). but cant rember, so i say stay with it becaus by ofering the switche it changes your mental state