4 ms·

The original article is more interesting and sheds light on the hidden assumptions that go into the calculation. It also considers under which sets of assumptio

The original article is more interesting and sheds light on the hidden assumptions that go into the calculation. It also considers under which sets of assumptions the answer is not 1/2. http://scienceblogs.com/evolutionblog/2011/11/08/the-tuesday-birthday-problem/ http://scienceblogs.com/evolutionblog/2011/11/08/the-tuesday... The attempt at shortening it down to under 300 words omits all the complications and subtlety involved in the problem.

willvarfar 13y ago
> Now, we should mention at this point that we are discussing mathematical children who have no existence outside the world of probabilistic brainteasers. So we’re not worrying about the fact that a disproportionate number of children are born on Mondays and Tuesdays, since C-sections aren’t usually scheduled for the weekends. We’re also not worrying about twins or triplets. Or any other sort of “real world” consideration that might occur to you. The one that occurred to me is that the probability of getting a boy or girl is not 50%, and the probability of getting two same-gender children is not 50% either. Here are some nice real stats: http://www.in-gender.com/XYU/Odds/Gender_Odds.aspx http://www.in-gender.com/XYU/Odds/Gender_Odds.aspx
kevinjones 13y ago
I also thought the original article was better, and clearer. As you say—it's the hidden assumptions which are interesting. In maths exams at school the problems are always presented in the form of: "a random family was chosen from ...". (Similar to "a smooth cube is resting on a smooth surface". In real life, it's more difficult. The original article looks at real life, whereas the 300-word version has reduced it to the exam version. Of course it's "easier" to understand the exam version, but this wasn't the point.

4 ms·

The original article is more interesting and sheds light on the hidden assumptions that go into the calculation. It also considers under which sets of assumptio

by archgoon 13y ago

willvarfar 13y ago
> Now, we should mention at this point that we are discussing mathematical children who have no existence outside the world of probabilistic brainteasers. So we’re not worrying about the fact that a disproportionate number of children are born on Mondays and Tuesdays, since C-sections aren’t usually scheduled for the weekends. We’re also not worrying about twins or triplets. Or any other sort of “real world” consideration that might occur to you. The one that occurred to me is that the probability of getting a boy or girl is not 50%, and the probability of getting two same-gender children is not 50% either. Here are some nice real stats: http://www.in-gender.com/XYU/Odds/Gender_Odds.aspx http://www.in-gender.com/XYU/Odds/Gender_Odds.aspx
kevinjones 13y ago
I also thought the original article was better, and clearer. As you say—it's the hidden assumptions which are interesting. In maths exams at school the problems are always presented in the form of: "a random family was chosen from ...". (Similar to "a smooth cube is resting on a smooth surface". In real life, it's more difficult. The original article looks at real life, whereas the 300-word version has reduced it to the exam version. Of course it's "easier" to understand the exam version, but this wasn't the point.