Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: Really confusing question.

  
  1. #1
    Status
    Offline
    !Simon's Avatar
    AOC Fanatic
    Join Date
    Mar 2008
    Posts
    946
    Mentioned in
    0 Post(s)
    Quoted
    1 Post(s)

    Really confusing question.

    Just seen this on another forum and even though I've seen why I'm wrong I still don't believe that I'm wrong.


    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 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 switch your choice?

  2. #2
    Status
    Offline
    stephenmelody's Avatar
    AOC Obsessed
    Join Date
    Feb 2007
    Posts
    1,435
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    This is off a film. Good Will Hunting maybe? Can't remember. Might have Robin Williams in it.

    I think you're supposed to stick as there is a 66% chance you were right, as 33% chance has been removed, so that 33 is added to the original 33%

    But to be honest, I can't really remember. You might be supposed to switch, as the 33% now rests on the other door...
    1.9 cdti (120) black ASH
    Wanted: Black VXR Grille!!

  3. #3
    Status
    Offline
    mdpburn's Avatar
    AOC Obsessed
    Join Date
    Feb 2009
    Posts
    1,602
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    makes no difference odds are now 50-50 right??

  4. #4
    Status
    Offline
    12vMatt's Avatar
    AOC Obsessed
    Join Date
    Sep 2008
    Posts
    1,465
    Mentioned in
    1 Post(s)
    Quoted
    0 Post(s)
    Quote Originally Posted by mdpburn View Post
    makes no difference odds are now 50-50 right??
    thats what i would have thought

    never change your door/box/whatever else anyway - stick with what you picked first
    Flame Red 2002-02 Mk4 1.6 SXi RIP
    Flame Red 1997-R Corsa 1.4 8v
    Back in an Astra Silver 2000-X Mk4 CD 1.6 16v

  5. #5
    Status
    Offline
    stephenmelody's Avatar
    AOC Obsessed
    Join Date
    Feb 2007
    Posts
    1,435
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    Yeah, because originally you had a 33% chance of getting it right, the other box still has 33% chance of being right, therefore the %age increases on the box you've chosen....

    I think. But I'm no mathematician.
    1.9 cdti (120) black ASH
    Wanted: Black VXR Grille!!

  6. #6
    Status
    Offline
    !Simon's Avatar
    AOC Fanatic
    Join Date
    Mar 2008
    Posts
    946
    Mentioned in
    0 Post(s)
    Quoted
    1 Post(s)
    Worth watching the whole video. It's logical BUT I still feel they have left out some factors.


    Click here if you cannot see the above video...

  7. #7
    Status
    Offline
    12vMatt's Avatar
    AOC Obsessed
    Join Date
    Sep 2008
    Posts
    1,465
    Mentioned in
    1 Post(s)
    Quoted
    0 Post(s)
    I've just watched all of that video.

    I can see where their logic is coming from BUT once there has been a door opened there are only 2 doors to pick from so therefore I would say that there is a 50/50 chance of getting the car as there is 1 door with a car and 1 wit a goat. the door that has already been opened is completely irrelevant at this stage.

    just my opinion on the subject (its a long time since ive done anything relating to probability)
    Flame Red 2002-02 Mk4 1.6 SXi RIP
    Flame Red 1997-R Corsa 1.4 8v
    Back in an Astra Silver 2000-X Mk4 CD 1.6 16v

  8. #8
    Status
    Offline
    danny's sxi's Avatar
    AOC Obsessed
    Join Date
    Sep 2008
    Posts
    2,473
    Mentioned in
    0 Post(s)
    Quoted
    0 Post(s)
    if their are 3 doors you have a 33% chance, he then opens one door leaving to doors closed. asking you to pick again gives you 50% chance. i think thats how it works anyway

  9. #9
    Status
    Offline
    !Simon's Avatar
    AOC Fanatic
    Join Date
    Mar 2008
    Posts
    946
    Mentioned in
    0 Post(s)
    Quoted
    1 Post(s)
    Quote Originally Posted by 12vMatt View Post
    I've just watched all of that video.

    I can see where their logic is coming from BUT once there has been a door opened there are only 2 doors to pick from so therefore I would say that there is a 50/50 chance of getting the car as there is 1 door with a car and 1 wit a goat. the door that has already been opened is completely irrelevant at this stage.

    just my opinion on the subject (its a long time since ive done anything relating to probability)
    Exactly my point. Surly the probability resets itself when one door is open but then again.... actually I dunno. I only did probability and statistics about half a year ago.

  10. #10
    Status
    Offline
    buckle's Avatar
    /
    Join Date
    Sep 2004
    Posts
    18,921
    Mentioned in
    0 Post(s)
    Quoted
    1 Post(s)
    Once you have watched the video is does make sense why you should swap. Your more likely to pick a goat when you chose the 1st door, so by swapping you then get the car.

Page 1 of 2 12 LastLast

Similar Threads

  1. Confusing oil leak !!!!!
    By mossy88 in forum Turbo Petrol Engines inc. Transmissions
    Replies: 28
    Last Post: 21-01-2011, 21:02
  2. confusing ecu
    By benhavenhand19 in forum NA Engines (Non-turbo petrol) inc. Transmissions
    Replies: 8
    Last Post: 01-01-2010, 16:22

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •