Personality and zip code can help explain differences in political ideology, according to a new study from Northwestern University, which is the first to show the relationship between a person's personality traits and political preference varies, depending on where one lives.
The researchers sought to determine whether the relationship between personality and political beliefs looks the same across the U.S., or whether it changes depending on the locally prominent ideology of the area in which the person lives.
They found people who have certain personality traits, including high levels of agreeableness (compassionate, kind, empathetic, cooperative) and extraversion (sociable, reward-driven), were more likely to align with the political beliefs of the local community.
"Individuals showing personality traits associated with high motivation to get along and get ahead in social environments are more likely to be conservative if they live in a more conservative community and more liberal if they live in a liberal community," said corresponding author Kayla Garner, a Ph.D. student in psychology at Northwestern. The study's senior author is William Revelle, psychology professor and faculty director of the Personality, Motivation and Cognition Laboratory of Northwestern.
Study significance
The large-scale study uses data from questionnaires submitted by more than 150,000 individuals across 8,700 zip code tabulation areas in the U.S. collected by the SAPA Project, a database developed in Revelle's lab.
The questionnaire, which collects between 44 and 300 data points from participants, measures the degree to which five widely accepted personality traits are expressed in an individual's responses. In addition to extraversion and agreeableness, the other traits are neuroticism (sensitivity, frequently experience anger, worry or sadness), openness (appreciates new ideas, feelings, behaviors), and conscientiousness (careful, hardworking, rule following).
While the researchers found correlations between political environment and traits such as conscientiousness, the most striking results were the flipped association between agreeableness, extraversion and conservatism.
For example, higher agreeableness was associated with higher conservatism in more conservative places, and higher agreeableness was associated with lower conservatism in more liberal places. Likewise, higher extraversion was associated with higher conservatism in more conservative places, and higher extraversion was associated with lower conservatism in more liberal places.
The study offers important insights for social scientists who study how ideology is formed and explains why research in this field, when it fails to account for social environments, finds inconsistent results regarding the relationship between personality and political ideology.
The findings also may help policy makers better communicate with constituents if they can understand why differences in political ideology occur across different geographic areas - and why polarization intensifies.
"If individuals higher in those 'getting along' personality traits are living in an area with a certain kind of belief, our study shows this influence may compound on itself because it aids people to get along and get ahead," Garner said.
"These findings demonstrate the importance and complexity of individual differences in personality, particularly the importance of large-scale studies across geographical regions," Revelle said. "Unfortunately, the tendency to get along can lead to divisiveness and polarization across groups."
Garner also sees the findings as humanizing during a polarizing time.
"It reminds us that people are trying to make the best of their environments, and get along the best they can," Garner said. "For individuals higher on certain personality traits, their political ideology may occur in large part due to what believing in something does for individuals' 'fitting in,' 'getting along' and 'getting ahead' in their local communities."
"Context specific personality associations with political ideology are shaped by geographical variation," was recently published in Nature Scientific Reports.
