Isn't this a result you should immediately be skeptical of because the results are so significant? I mean, the idea that you can detect sexual orientation from facial images seems somewhat plausible, but no way I would immediately buy that a classifier can discriminate just from the facial-structure with 81% accuracy as the title may imply, for instance. To be fair, in their abstract the authors mention grooming style and so on, but I feel that the title alone is slightly misleading.

Also: man, that preprint formatting is annoying to read.