On May 13, 2:27*pm, (Dave Platt) wrote:
In article ,

Don Pearce wrote:
or you can choose the other door. *The car is behind one of them.
50-50.

No, you are in fact choosing one door (your first choice) or BOTH the
other doors - the choice if you swap.

Thank you, Don! *Describing the problem in that way is without a doubt
the clearest explanation of the "paradox" I have ever read.


This explanation (by subtraction) from the wikipedia article struck
me:

"An even simpler solution is to reason that switching loses if and
only if the player initially picks the car, which happens with
probability 1/3, so switching must win with probability 2/3 (Carlton
2005)."

The player picks a door and has a 1/3 chance of being right. This
chance does not change when a losing door is revealed, so the only
remaining choice gives you a 2/3 chance.