New research suggests that you may have more personality traits in common with your friends and partners than previously thought.
Previous studies have already shown that friends and romantic partners often share certain characteristics such as age, education, and intelligence. Although it makes sense that they would be also similar in personality, with sharing likes and dislikes forming the basis of a relationship, first author on the new study Youyou Wu of the University of Cambridge and Northwestern University commented that, "Surprisingly, decades of research had found no evidence."
Wu, along with researchers from Stony Brook University in New York state and Stanford University in California, used a Facebook app called MyPersonality to collect Facebook data and personality questionnaire scores from 295,320 participants.
Using the data and statistical models, the team assessed personality traits from Facebook "Likes" and status updates.
Their findings revealed significant similarity in personality between friends and between romantic partners.
"We found that, on self-report questionnaires, couples are no more similar than strangers, but when we measured personality using digital behavior -- Facebook Likes and status updates -- couples were far more similar than chance," explains co-author David Stillwell, "So, people date and befriend others who are like themselves, and birds of a feather do flock together after all."
The team believe that previous studies had failed to find an association as they had asked individuals to rate their own personality traits using self-report questionnaires.
"When people answer questions such as 'Are you well-organized?,' they naturally end up comparing themselves to those around them," said co-author Michal Kosinski, "In other words, if you are surrounded by very well-organized people, you may judge your own conscientiousness more harshly. Conversely, a relatively messy individual, living in a dorm filled with others who are even messier, might see herself as a beacon of cleanliness and order."
Wu explained how their approach to avoid such bias: "People who like 'Salvador Dali' or 'meditation', for example, tend to score high on openness to new experiences; those who write about 'partying' or 'weekends' a lot tend to be extraverted. The advantage of this approach is that everyone is being judged against a universal standard, leaving less room for subjective judgment."
However the team did add that although their study found that friends and partners are more similar than previously thought, the findings do not explain what is the causal order, and whether people are attracted to each other because of common traits that already exist or whether they become more like each other over time.
The findings can be found published online in Psychological Science, a journal of the Association for Psychological Science.