Gender equality
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Abstract
Standard University (I am making this up) wanted to make sure it was admitting students in a way that's fair to males and females. So SU told its two departments, A and B, that the proportion of male and female acceptances must be the same as the proportion of male and female applicants. Department A had 100 male and 100 female applicants. It could accept only 100 new students, so it accepted 50 males and 50 females; it accepted 50% of the male applicants, and 50% of the female applicants, fulfilling its obligation. Department B had 100 male and 900 female applicants. It could accept only 100 new students, so it accepted 10 males and 90 females; it accepted 10% of the male applicants, and 10% of the female applicants, fulfilling its obligation. That means that SU had 200 male and 1000 female applicants, and it accepted 60 males and 140 females; it accepted 30% of the male applicants, but only 14% of the female applicants, which is unfair. Where did they go wrong? They didn't do anything wrong. There is no way to accept students that's fair to all of SU and Department A and Department B. No matter what SU does, it will be accused of gender unfairness.