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Message: [QUOTE="SWC75, post: 5083005, member: 289"] From my initial post: [I]Two theories: - You take away one option, you are left with two options. It must be 50-50, right? - You have a 1/3 chance it's behind the first door and that doesn't change just because it's not behind the third door. I will go to my grave thinking that the first theory makes the most sense. What if you started out with two doors, had the contestant chose one of them, then wheeled out a third door, opened it and there was a goat there. Would that have made it a good idea for the contestant to switch? Isn't that the same situation? I decided to test it with a deck of cards. I separated the black and red cards. The black cards are cars, the red goats. I combined one black card with two red cards. I shuffled the three cards as best I could. I took the first three and put them face down. I 'chose' #1 and flipped the third card over. if it was black, I put those three cards aside. If it was red, I then flipped the second card and recorded when it was black and when it was red. I had, as I recall 10 of 13 sets where the third card was red and the second card was black 7 times. I reshuffled them and did it a gain a couple more times and the 2/3 percentage held. I then realized that I was wrong but still don't understand why.[/I] I've understood the 1/3 vs. 2/3 theory all along. When I first checked it with the card game some years back, I saw that that's how it worked out and accepted it but I still didn't see why the game doesn't change to a two door game with a 50-50 chance when you eliminate one door. My current efforts, which are now a much bigger sample than I looked at then, suggests it does change. Each time the third card comes up red, (a goat), it comes down to how often the black card, (the car) is the first card or the second. That's the Monte Hall situation. I just played the card game again and, of 26 hands, 9 of them had the car behind the third door and thus were not the Monte Hall situation. Of the other 17 hands, the second card was the black one 9 times. The first card was black 8 times. Virtually 50-50. For the three games, I'm 29-24 in Monte Hall situations, (the #1 card has bene black 29 times when the third card was red). [/QUOTE]

Verification: What is a Syracuse fan's favorite color?