tag:blogger.com,1999:blog-9142025972629449791.post43969867834384095..comments2016-12-14T11:05:32.430+00:00Comments on Armchair Biology: A Nice New ParadoxArmchair Biologisthttp://www.blogger.com/profile/16528412260692313555noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-9142025972629449791.post-89484078553468974452013-03-09T16:04:55.682+00:002013-03-09T16:04:55.682+00:00Thanks JeffJo, but I understood you the first time...Thanks JeffJo, but I understood you the first time. Repeating your point won't help: it's correct, and I see that it's correct, as I said in my reply above.<br /><br />L.Armchair Biologisthttp://www.blogger.com/profile/16528412260692313555noreply@blogger.comtag:blogger.com,1999:blog-9142025972629449791.post-19899252169219750092013-03-09T13:04:20.381+00:002013-03-09T13:04:20.381+00:00But the whole point is that stating "one is a...But the whole point is that stating "one is a boy," and being compelled to say whether one is a boy, are quite different things. And it is the very act of compelling that causes the unexpected probability fluctuations as facts are added to what is being compelled.JeffJohttp://www.blogger.com/profile/09110352332876400907noreply@blogger.comtag:blogger.com,1999:blog-9142025972629449791.post-79326149773899851242013-03-08T18:40:08.487+00:002013-03-08T18:40:08.487+00:00Thanks for the comment, JeffJo.
You really made m...Thanks for the comment, JeffJo.<br /><br />You really made me think about what's going on with the wording of that simple puzzle. I agree: you're correct so long as the parent of a BG/GB family has the opportunity to name either the boy or the girl, and ask the appropriate question (even if phrased as 'I do not have two boys').<br /><br />In my defence, I was explicit about my Armchair Biologisthttp://www.blogger.com/profile/16528412260692313555noreply@blogger.comtag:blogger.com,1999:blog-9142025972629449791.post-49796497572642967972013-03-06T14:48:17.096+00:002013-03-06T14:48:17.096+00:00Q1) A parent is chosen at random from a large set ...Q1) A parent is chosen at random from a large set of two-child families. What is the probability that both of his/her children have the same gender?<br /><br />The answer is simple: 1/2.<br /><br />Q2) Another parent is chosen at random from the subset of these families that include at least one boy. What is the probability both children have the same gender (which, by necessity, must be "JeffJohttp://www.blogger.com/profile/09110352332876400907noreply@blogger.com