>Dan
>
>When you choose the first time: you have a 33% chance of getting the car whichever door you choose. But it doesn't matter, because Monty changes the test and invites you to try again.
>
>When you choose the second time: you have a 50% chance of getting the car whichever door you choose.
>
>Only the 50% matters. Your previous choice has no impact on this whatsoever. One door has a car and one a goat no matter what you did the first time.
>
>
>Regards
>
>JR

I'd believe it if in the example, below with the cards you're odds played out. I understand it looks like a 50/50 but it really isn't. Another point that Steve Gibson made is that if Monty had no knowledge of what was behind the doors and just randomly chose a door, it truly would be 50/50, but 50% of the time Monty would show the wrong door ( with the prize ) and the game would end.

I can't get passed the logic of the cards. 33% of the time I switch I lose and 66% of the time I win. I've done this with a deck of cards a number of times and it plays out close that 66% of the time.

This is a well known statistical problem, don't take my word for it. Do some research and you'll see page after page of documentation on it.