The test seems kind of bogus but I don't know anything about statistics or machine learning - they always processed two photos at a time and one was guaranteed

The test seems kind of bogus but I don't know anything about statistics or machine learning - they always processed two photos at a time and one was guaranteed to be self identified as gay and the other was always heterosexual. It seems like one would really need to have the test work in any combination of cases, not just the one they used where there was always one of each type of sexuality.