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Afaict tell the initial range of possibilities is: GG GB BB The relative ages of the children play no part, they could be twins for all I care. So the initial
by glenngillen 13y ago
Afaict tell the initial range of possibilities is:
GG GB BB
The relative ages of the children play no part, they could be twins for all I care. So the initial probabilty of being BB is 1/3. Knowing one of them is a boy then removes GG as an option, and the probability for BB unsurprisingly becomes 1/2.
What am I misunderstanding in this problem?
- aytekin 13y agoIt matters if the assumption is that possibility of each child being boy/girl is 50%. The first child can be boy or girl. The second child can also be boy or girl. So the probabilities are like this: BB: 25% GG: 25% BG: 50% You can replace older/younger on the article with child 1/child 2.
- te 13y agoThat GB is twice as likely as either GG or BB. For this reason, reference is made to BG to make this more apparent.
- gametheoretic 13y agoYou only misunderstand because the author is presenting it stupidly (as you state, incorporating order where order is irrelevant), leading to his own stupid conclusion. Read my post elsewhere in the thread for the full explanation, and if you find this kind of thing interesting, look up the Monty Hall problem (the point of which is that changing the information changes the odds).