[jldugger]

This is twisting my brain a bit -- there's a third possible version, where the only info you have is the day of week. Something like "i have a child, one of whom was born on tuesday. what are the odds the other is a boy?" perhaps.

And the answer there has to be basically 50:50. So when you combine these two filters, day of week wins somehow. Will have to ponder more

[jspiral]

ah i didn't actually explain it, the other responder did though. 6/7th (~85.7%) of parents with b g are knocked out by the day of week filter, while only ~%73.5 of the b b parents are knocked out by it. (if i did that math right) so proportionally the sample has more bb parents than the one without day of week.