There are ways to measure compatibility, though some are obvious, and perhaps unfair ways of judging a habit that might be broken. Kissing comes to mind, as well as something as standards as going through a list of likes and dislikes.
Personally, I prefer something more fool-proof.
Now, you may want to issue potential suitors Myers-Briggs tests, drugs tests, IQ tests, or road tests. I prefer a new method: Cooking. I call it the Breakfast Test. Just make eggs, potatoes, and toast. Keep track of what bread they choose and how well they can scramble eggs. Watch them slice an onion and cook it down for the home fries. Pour juice. See if they burn the bottom of the pans or ruin the toast. In half an hour, you’ll end up with a mess or a romance. Either way you get brunch out of it, which is more than I can say for most pop quizzes.