Representational image.

Tyler Cowen, Tribune News Service

In my travels around the US, I am often struck by America’s regional differences. I don’t mean people’s politics, cuisine or customs. I am referring to their personalities. Are some parts of the country more outgoing than others? More conscientious? More neurotic?

We all have our intuitions about such questions. But a more systematic look at the data has just been published. And the answer is clear: Yes, American personalities do differ by region.

The researchers considered five personality traits, taken from what is called Five Factor Personality Theory: extraversion, agreeableness, conscientiousness, emotional stability (there is a related concept of “neuroticism”) and openness. Those concepts have formal definitions in social psychology research, but for our purposes the common-sense meanings of those words are close enough.

Let’s consider extraversion. The least extroverted states in the country are Maine, Washington and Oregon, which fits my stereotype that a disproportionate number of the residents of those states are seeking some kind of isolation.

Wisconsin has the most extroverted population, with Illinois, Iowa and Nebraska coming in next. The Midwest seems to be a friendly and outgoing place. That is to me also no huge surprise, though I would not have picked Wisconsin to be No. 1. The southern states come in at about average, while New Mexico, Nevada, Vermont and Montana do not measure as very extroverted, relative to the rest of the country.

So far so good: My basic intuitions have been validated with data.

How about agreeableness? The Southeast measures as the clear winner, with pockets of the Dakotas and Minnesota also high on the scale. Again, that is consistent with my expectations. Wyoming, Nevada and the area surrounding northern Texas are clustered at the bottom of the agreeableness scale. (By the way, agreeableness isn’t necessarily a good thing. Data on labor market outcomes, for instance, suggest that more agreeable men suffer an earnings penalty; perhaps they do not bargain as hard.)

The data on conscientiousness run counter to stereotype. My expectation was that the Midwest would win out here, but the Southeast ranks the highest. Coastal California fares poorly, as do scattered parts of the Midwest and West, again non-obvious or unexpected results. If it restores your faith in stereotypes, the area surrounding New Orleans, perhaps the most licentious city in the South, also rates low in conscientiousness.

Overall, the two strongest correlates of conscientiousness were Republican share of the vote, and share of married individuals in the population.

When it comes to emotional stability, fans of “The Sopranos” or “Seinfeld” will not be surprised: The Northeast, stretching down through Appalachia, ranks the lowest by a noticeable amount. There’s a reason George Costanza and Tony Soprano fit right in.

As for openness, the West measures as more open than the East, which again seems to correspond to the stereotype. The exception is Florida, which rates as very open, and the northern Midwest comes in last. Perhaps they are too busy being extroverted (see above) to be open to new experiences! Among the factors predicting openness: share of foreign-born citizens, creative industries and share of the population with college degrees.

Predictions and correlations work better at the county level than the state level, which implies that most states are diverse places; San Francisco and Death Valley are quite distinct, and all states have numerous divisions and subcultures. That’s one reason why I don’t see the breakup of the United States as likely anytime soon.

People can and do debate just how much weight to place on the results of personality psychology. These ratings of personality characteristics rely on potentially unreliable individual self-reports.

Yet these measured characteristics have predictive power in a variety of circumstances, and the core results of this literature replicate. As a case in point, I would describe myself as an introvert, and most of those who know me would agree. Whatever our self-deceptions may be, most of us have at least partial awareness of our own personalities and are willing to present them as such.