The Census Bureau’s participation map made quite a splash last week. More than half of Americans (56 percent) had completed their forms by April 5, but there was tremendous variation across the 50 states. Wisconsin topped the list with 69 percent of Wisconsinites sending in their forms. Midwestern states did well across the board with more than two-thirds of Iowans and Minnesotans completing theirs. At the opposite end of the spectrum, less than half the residents of Alaska, Texas, New Mexico, and Louisiana completed theirs; 50 percent of New Yorkers had filled out their forms and 51 percent of D.C. residents.

But what factors might drive Census participation? With the help of my colleague Charlotta Mellander, I decided to take a quick look. We examined the correlations between Census participation and economic factors, demographic characteristics, and state personality traits. This analysis is based on simple correlations which identify associations between variables but do not specify causality. I also spoke to my colleague and collaborator, the Cambridge University personality psychologist Jason Rentfrow about these results.

The short answer is that in terms of who fills out Census forms, personality is the only thing that seems to matter. We found no correlation between Census participation and key economic and demographic variables like income, economic output, education level, or type of jobs. But we found some considerable correlation between states where more people filled out their Census forms and three of what psychologists term the Big Five personality types – especially in states with high concentrations of agreeable people, extraverts, and open-to-experience types.

States with large concentrations of agreeable people were most likely to complete their Census forms (with a correlation of .43). Rentfrow says: “Agreeableness reflects a tendency to avoid conflict and to cooperate, so it makes sense that regions with large proportions of agreeable people would do what was asked of them and return their Census forms on time.”

States with large concentrations of extraverts were also more likely to complete their forms (with a correlation of .37). “One aspect of extraversion is the tendency to be expressive and reveal information about oneself,” notes Rentfrow. “So perhaps people in extraverted regions are more comfortable revealing personal information about themselves as compared to places where people are introverted and private.”

Conscientiousness comprises traits like responsibility, discipline, and obedience, so one would think that states with high concentrations of these more diligent types would be more likely to fill out their forms. But that’s not what we found. The correlation between conscientious personality types and Census participation was positive (in the range of .2)  but not statistically significant.

States with high concentrations of open-to-experience people were less likely to have their forms filled out. The correlation for all 50 states is negative but not significant in statistical terms. When we remove Alaska, which is an outlier, from the analysis, the correlation is stronger and statistically significant (-.34). Openness is a disposition toward creativity and originality. So in highly open regions, substantial numbers of people may be so focused or preoccupied with generating their next new idea – writing their latest essay, making that short film, forming a new band, or just chasing after the latest, greatest experience – that they put off their Census forms. Or, Rentfrow adds, “People high in openness tend to be unconventional and to challenge the status quo, so one possible explanation for this finding is that more people in open regions may question the legitimacy or utility of the Census.”

That leaves the neurotics. Census participation is negatively associated with neurotics, but the relationship is not statistically significant.

Ultimately, when it comes to completing the Census form, our correlations show that it’s not economics, education, or types of employment of a state that seem to matter. Personality ends up being a bigger factor, at least according to our provisional analysis. Rentfrow provides some useful context: “Completing the Census form is not just about reporting one’s age, sex, race, income, education, or occupation. It asks people to reveal something about who they are, and not everyone is comfortable or compelled to do so. Research in psychology provides some clues about which people would be likely to feel comfortable or obliged to complete their forms, and the state personality data provides a map of where those people live.”

Yesterday, we looked at the relationship between drug use and the concentrations of certain kinds of jobs in states. We saw that cocaine is more likely to be used in states where lawyers make up a larger share of the workforce, while marijuana use is associated with states with higher concentrations of artists, scientists, architects, and educators.

Today, we turn to the relationships between drug use and personality. Psychologists define personality according to the five types – extraversion, agreeableness, conscientiousness, neuroticism, and openness-to-experience. A study by psychologists Jason Rentfrow, Sam Gosling, and Jeff Potter has developed and analyzed data on the state-wide concentration of these five major personality types. Charlotta Mellander and I then worked with Rentfrow to examine the relationship between drug use and the state-wide concentration of personality types. The charts below graph the results.

Basically, drug use was positively and significantly associated with one personality type – openness-to-experience (.33**). It was negatively and significantly associated with three others – agreeableness (-.41**), conscientiousness (-.29*), and extraversion (.-52**).

Rentfrow explains our results this way.

I find it helpful to think about these regional differences as reflecting different psychosocial climates/scenes, and one question we can ask is what underlies these climates/scenes?

Openness, for example, is associated with curiosity and trying new things, so it would make sense that Open regions are places where more people have experimented/used drugs than places low in Openness.

Conscientiousness is associated with order, structure, caution, and obedience, so it would make sense that there would be less experimenting with drugs in places where there are large numbers of conscientious people.

Low levels of agreeableness are associated with aggression and antisocial behavior, so it’s conceivable that places with large numbers of disagreeable people will also be places with comparatively high drug use.

The one dimension that is inconsistent with what I would expect is Extraversion. Hans Eysenck proposed that extraversion is driven by arousal. Whereas introverts have higher levels of internal arousal, which motivates them to avoid social contact because it generates more arousal, extraverts are low in internal arousal and seek out stimulating activities to increase their level of arousal (it’s like introverts are anxious and avoid stimulation and extraverts are bored and seek it out). With that in mind, I was expecting to see that stimulants were more commonly used in places where Extraversion is high and that marijuana was used more in places with fewer extraverts. That’s not what we’ve found, though.

Correlation coefficient: .38**

Correlation coefficient: .38**

Correlation coefficient: .40**

Correlation coefficient: -.52**

Correlation coefficient: -.41**

Correlation coefficient: -.29*

Note: * indicates statistical significance at the .05 level; ** indicates significance at the .01 level.

MapScroll links to a series of “new and improved” maps of Big Five personality types from the expanded (Canadian) edition of my book Who’s Your City?. Based on data collected by Cambridge University psychologist Jason Rentfrow and his collaborators, these new maps ignore state and national boundaries and include the U.S. and Canada.

The first map is agreeable types.

The second is conscientious personalities.

The third is for extroverts who are more likely to move according to Rentfrow and company’s research.

The fourth is for open-to-experience personality types, also more likely to move.

The fifth is for neurotics.