how would you explain the right answer to the doors problem?
okay, so:
to recap: three doors. prize behind one of them. you pick one, then one of the doors you didn't choose is opened to reveal there's nothing behind it. do you switch to the other closed door?
explanation A:
I'm assuming nobody needs to be told the odds of picking right first time is 1/3. let's call the door you picked door A. before the empty door is opened, there are three scenarios, each with a 1/3 chance to happen: the prize door is either A, B, or C. in the 1/3 of circumstances where it's A, a random other door is opened, and you shouldn't switch. in the other 2/3, the door that doesn't have a prize behind it opens, and you should switch. given you have no other information than what door was opened, you're better off assuming you're in the 2/3s of cases where you should switch rather than the 1/3 where you were right first time.
explanation B:
consider an alternate scenario where there are 100 doors. the odds of picking the right one first are 1% right? and the person opening the doors a) knows the prize door and b) cannot open the door you already chose. so what's more likely; you chose right with your 1% guess, or the other door, which has survived 99 rounds of culling, is the prize door?
the thing that matters here is that the doors being opened are not random, and that you picking a door insulates it from the pool









