Under the roll and closer to the wall? Or do you hang your toilet paper over the roll?

Well, a new study suggests there are two types of people in the world: normal, sane, functioning human beings who hang toilet paper in the “over” position, and psychopaths who hang it in the “under” position to make life miserable for themselves and whoever else uses their throne.

Seriously, you should know that there’s a documented correct way to place toilet paper onto the holder — which is in the “over” position.

Relationship expert and TV therapist Dr. Gilda Carle created a personality test to show that there are some serious personality differences between over-people and under-people, like the fact that under-people clearly enjoy the sight of their toilet paper unspooling from the awkward and wrong direction.

In the Toilet Paper Personality Test, 2000 men and women, aged 18 to 75 of different ethnicities, were surveyed on which way they roll their toilet paper, and on how assertive they are in their relationships on a scale of 1 to 10.

Hang your roll like this? Apparently you’re a dominant person.

Prefer to go under? It’s thought that you’re a submissive type.

The results revealed that those “who roll over are more dominant than those who roll under,” meaning they have a Type-A personality. Under-rollers are the opposite, being more submissive and laid-back.

The study also found that one in five will actually change the way the toilet paper is hung even when in someone else’s home.

Now that’s dedication.