Ah, OK, I see the original puzzle. Jonathon is right: with the new
information you now know that the good door is one of the remaining two.
While the odds HAVE changed, from 1-in-3 to 1-in-2, switching your choice
will neither increase nor decrease the odds of picking the right one.
Amazing that anyone would think it might...
Lawry
> -----Original Message-----
> From: owner-moq_discuss@venus.co.uk
> [mailto:owner-moq_discuss@venus.co.uk]On Behalf Of Jonathan B. Marder
> Sent: Thursday, July 11, 2002 8:25 AM
> To: moq_discuss@moq.org
> Subject: RE: MD Let's Make a Deal
>
>
> Hi Rick, Erin, Glenn,
>
> I've been in a discussion on this before. The fact that Monty provides
> new information DOES change the statistics. You now know that door #1 is
> worthless, so the stats are as they would be if you knew that in the
> first place - it's 50/50 on door #2 vs. #3.
>
> The interesting thing about the previous debate I saw on this was that
> nobody could agree on the solution . . . until someone ran a simulation
> and confirmed empirically that the chance of guessing right is indeed
> 50%. So much for theory!
>
> Jonathan
>
>
> ---Original message from Rick [VALENCE] ---
>
> Here's the Setup:
> Imagine you're a contestant on Let's Make a Deal. Monty Hall calls
> you up to the stage and explains the game to you. He tells you there
> are three doors. Door #1. Door #2. And Door #3. Behind two of the
> doors (he won't tell you which of course) are worthless gag prizes, but
> behind the third is a valuable prize (for this group, we'll imagine it's
> an unlimited one-on-one Q&A with Robert Pirsig as he sails you down the
> Hudson River on the Arête).
> Monty asks you choose a door... you pick door #2. Monty says, "Well
> it's a good thing you didn't pick door#1." Door#1 opens and you see one
> of the gag prizes revealed (let's say... a goat in a wheelbarrow).
> Now you're down to your chosen door (door#2) and the remaining door
> (door#3). Monty says, "I'll give you $100 to switch to door#3.... I'll
> give to $200...$300...etc...etc."
>
> Here's the Question:
> Does switching doors improve your odds of winning?
>
> Here's the Possibilities:
> 1. Switching won't help. It's a 50/50 chance. Door #2 or Door #3.
> Switching don't mean diddley.
>
> 2. Switching will help. You started with 3 doors. 2 bad and 1 good.
> Odds are, you picked a bad one to begin with. So odds are, if you
> switch, you're switching to a good one.
>
>
>
> Can anyone crack this one for me? Does switching improve the odds?
>
>
> thanks,
> rick
>
>
>
> MOQ.ORG - http://www.moq.org
> Mail Archive - http://alt.venus.co.uk/hypermail/moq_discuss/
> MD Queries - horse@darkstar.uk.net
>
> To unsubscribe from moq_discuss follow the instructions at:
> http://www.moq.org/md/subscribe.html
>
MOQ.ORG - http://www.moq.org
Mail Archive - http://alt.venus.co.uk/hypermail/moq_discuss/
MD Queries - horse@darkstar.uk.net
To unsubscribe from moq_discuss follow the instructions at:
http://www.moq.org/md/subscribe.html
This archive was generated by hypermail 2b30 : Sat Aug 17 2002 - 16:02:25 BST