Monty Hall

[andrewducker]

[Poll #1770413]

Explanation

I have known what the answer was for ages, but for some reason it only "clicked" in my head today. You can blame sarahs_muse for triggering it.

Comments

[chuma.livejournal.com]

I'm not repeating myself further. Come back when you have found something online on the problem, along with an apology when you realise you are wrong.

[theweaselking.livejournal.com]

You probably should have googled it yourself. It's an old, old problem, and I didn't even change the words on it the way I did with the raptor babies.

The raptor babies? That's the Boy Or Girl Paradox.

[chuma.livejournal.com]

Have you actually READ that link? Because it confirms what I said.

It even explains where you are wrong due to the ambiguity.

"From all families with two children, at least one of whom is a boy, a family is chosen at random. This would yield the answer of 1/3."

"From all families with two children, one child is selected at random, and the sex of that child is specified. This would yield an answer of 1/2."

You stated clearly that "I've checked the first one, and it's female!" in the question which is the same as the 2nd statement.

You see the difference between one of them is female and AT LEAST one of them is female?

[theweaselking.livejournal.com]

"One is female, one is unspecified, and they're not ordered" is the same as "at least one is female".

And you probably should have checked on the problem clarification, or listened to any of the explanations - or, y'know, simply not claimed that "It's not 1" meant "4 is twice as likely as before" so many times.

[chuma.livejournal.com]

You clearly state that the head scientist only looked at the first one and it was female. Don't come back trying to throw the blame because you got it wrong. Most of the article you linked talks about the ambiguity in detail and yet you clearly didn't take it in.

You are wrong. It IS 50%. You own article explains why.

[theweaselking.livejournal.com]

You clearly state that the head scientist only looked at the first one and it was female.

More, that the first one the scientist checked was female. Clarified, again, repeatedly, to everyone's satisfaction, three hours ago.

I don't understand why you seem to be taking this so personally. Did Bob and Sue kick your dog or something?

[chuma.livejournal.com]

Because you are being so patronising and yet you are wrong. That you have proven yourself wrong with your very own link only serves to make you seem even more of an arse on the subject.

Even the Bob and Sue link is filled with people pointing out the problems with the wording. It is ambiguous as to whether we assume that sue always rolls a 1-5 or whether we take all of the games possible and only look at the percentage of those where Bob wins.

Your problem seems not to be maths, but english.