I've never understood this problem
In that the way people try to explain the problem and don't clearly explain whether things are independent or not in the scenario they create. As soon as you stress that in this situation they aren't independent because the gameshow host knows what's behind all doors, always will choose the goat and bases his decision on that it becomes a bit clearer...
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Herman Blume is unique, just like everyone else, Fri 4 Mar 2011, 8:28,
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It always made sense to me
if the guy always picks a goat then you've either already got the car (1/3 chance) or you picked a goat (2/3 chance) so it makes sense to swap.
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Peej, Fri 4 Mar 2011, 9:58,
Reply)
Yep
The first choice you make has a 1\3 probability of being right, however the second has 1\2 probability. The higher probability means that you should always go for it.
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LemonEntryMyDearWatson This time, Moriarty, the hand is on the other foot, Fri 4 Mar 2011, 10:51,
Reply)