I've been observing how people arrange themselves on elevators. I'm sure that numerous peer reviewed studies have been done on this, but I'm enjoying my own informal research. My old building had a non-standard elevator, which tended to enforce an uncomfortable intimacy, and was particularly hard on the claustrophobic. Modern elevators, and their modern users, tend to arrange themselves with a high degree of predictability--As soon as you get on you arrange yourself in the back half of the cab. If your the first person on in a group you'll set up in the zone near the floor buttons and act as the car operator.
People who are experienced train users will exhibit a similar rational behavior. Inexperienced train users muck things up reliably.