Brandon mentions a test performed on NewYawkuhs and Southroners, to wit: The test had subjects walk down a hallway to "fill out some paperwork." A guy opens a filing cabinet to block their path, huffs, and closes it quickly while they walk by. The subject is then immediately tested for symptoms of stress (blood pressure, heart rate, etc.).
I heard of a similar test that has been run on NYCers and Memphians. They had someone accost people on the street asking for directions and the Memphians proved to be significantly more polite to the accosters. A resident of NYC, realizing that the tests, having been run in the respective cities, carried a certain bias so he reran the test but this time, to even things out a little, planted some street people to pre-accost the subjects in Memphis with demands for spare change and the like. This to simulate the NYC experience a little better. In the field leveled test the NewYawkuhs scored significantly better than the Memphians.
