A couple decides to keep having children until they have the same number of boys and girls, and then stop. Assume they never have twins, that the "trials" are independent with probability...
The net effect is that even if I don't know which one is definitely a boy, the other child can only be a girl or a boy and that is always and only a 1/2 probability (ignoring any biological weighting that girls may represent 51% of births or whatever the reality is).
Probability of having 2 girls and probability of having at least one girl Ask Question Asked 8 years, 8 months ago Modified 8 years, 8 months ago
Probability of having 2 girls and probability of having at least one girl
Considering the population of girls with tastes disorders, I do a binomial test with number of success k = 7, number of trials n = 8, and probability of success p = 0.5, to test my null hypothesis H0 = "my cake tastes good for no more than 50% of the population of girls with taste disorders". In python I can run binomtest(7, 8, 0.5, alternative="greater") which gives the following result ...
Use standard type for Greek letters, subscripts and superscripts that function as identifiers (i.e., are not variables, as in the subscript “girls” in the example that follows), and abbreviations that are not variables (e.g., log, GLM, WLS). Use bold type for symbols for vectors and matrices. Use italic type for all other statistical symbols.
Thanks to the answers I now understand why the ratio would be 1:1, which originally sounds counter intuitive to me. One of the reason for my disbelief and confusion is that, I know villages in China have the opposite problems of too high of boys:girls ratio. I can see that realistically, couples won't be able to continue to procreate indefinitely until they get the gender of child they want ...