21–30 of 33 posts
Earlier quoted context omitted.
That's the same reasoning I have. P(B|A) = P(B) for independent variables.
On the other hand, if a couple told you they had five kids, at least four are boys, you would say to yourself, "it's not very likely that any couple would have five boys", and you would be correct...
Consensus is clearly 66% or 50% depending on whether you think the GB and BG combinations are the same thing in the context of the question. But isn't it true that more boys than girls are born (because boys die younger so evolution tries to balance it out a bit)? Does anyone know if certain fathers can only produce one sex of child? If so then having one girl would increase the chances of having another girl slightl…
Although women may live longer they lose their ability to reproduce earlier so I would expect more girls than boys.
67%. The percentage of having one boy and one girl is 50%, "one of them is a girl" eliminate the condition of having two boy.
Except that real data seems to disagree with you - the chance is about 50%. http://www.in-gender.com/xyu/Odds/Gender_Odds.aspx
Who are you people and what did you do to HN.
My guess is 25% - 0,5 times 0,5..
But what exactly is the right answer? There doesn't seem to be a consensus yet.
Earlier quoted context omitted.
Except that real data seems to disagree with you - the chance is about 50%. http://www.in-gender.com/xyu/Odds/Gender_Odds.aspx
A link to an analysis based on an actual study was modded down? Who are you people and what did you do to HN.
However, I did not vote you down.
Take a random parent with two children. You ask them if at least one is a boy and they say yes. The probability that the other is a girl is 66.6% Take another random parent with two children. You ask them if the oldest child is a boy and they say yes. Now the probability that the other is a girl is 50%. This confuses people. (The point is the second scenario gives you more information since it's a subset of the first…
And although this problem is often used to show that humans are bad at doing probability in their heads, note how simple it is to do the probability calculation for the two scenarios that you've mentioned.
What's actually hard for humans is describing models or simulations, not doing the probability. Once you explained the possibilities for original problem in a more detailed way, the answer(s) becomes obvious.
Earlier quoted context omitted.
A link to an analysis based on an actual study was modded down? Who are you people and what did you do to HN.
The analysis you linked to does not refute anything said here. In fact, the conclusions of the study you showed are a necessary assumption for this problem (that each gender has an equal probability and independent of birth order). This problem has nothing to do with biology but rather using posterior information to come up with a probability given a statistical experiment. However, I did not vote you down.
Yeah, this is a famous puzzle. The answer is supposed to be 2/3, because what the question is asking you to do is consider all the parents in the world where at least one of the two children is a girl. Then you're left with 3 possibilities, BG, GB and GG. If you phrase the question like that, everyone will get the right answer. The reason people get it wrong is that people don't normally talk like that . Imagine you'…
This is by far the most insightful thing I have ever read about this problem. Furthermore, this being a site about startups, I would say that you will be more successful if you understanding people and math than if you just understand math.
Yeah, this is a famous puzzle. The answer is supposed to be 2/3, because what the question is asking you to do is consider all the parents in the world where at least one of the two children is a girl. Then you're left with 3 possibilities, BG, GB and GG. If you phrase the question like that, everyone will get the right answer. The reason people get it wrong is that people don't normally talk like that . Imagine you'…
The game-show version of the Monty Hall problem isn't ambiguous... people even had the chance to see the show before knowing the mathematical problem. I agree there are different ways to state the problem, but the wording doesn't explain why it confuses people.
I've tried explaining the problem to both people who've seen the show and those who haven't. My experience is that if you've seen the show you'll never accept the question, let alone the answer. Meanwhile, those who never watched the show can be convinced.
Earlier quoted context omitted.
Except that real data seems to disagree with you - the chance is about 50%. http://www.in-gender.com/xyu/Odds/Gender_Odds.aspx
A link to an analysis based on an actual study was modded down? Who are you people and what did you do to HN.