I don't know. I always found what people passively reveal in their various likes and dislikes, their mannerism, their choices, etc to be pretty accurate (but as a generalization).
Example: the kind of music they listen to, their favorite color, the car they drive (and the color of the car), movies they watch, their diet, their religion, political leanings, how they dress, their job and education, even their horoscope sign...and the list can go on.
Even I could be judged pretty precisely by much of the above measures.
My best example would be "Classical Music" and particularly "Opera" purists. You can read them like a book.
Lucky