The study was led by Roxane Cohen Silver, professor of psychology & social behavior. School of Social Ecology

Irvine, Calif., Aug. 17, 2016 – An alternative to using Twitter geotags and hashtags to identify community members who have experienced collective trauma, such as a school shooting, shows promise in helping researchers rapidly assess local effects. The approach, developed by researchers at the University of California, Irvine, was deployed to study the impact of deadly gun violence at UC Santa Barbara, Northern Arizona University and Oregon’s Umpqua Community College.

Followers of local Twitter accounts, such as the city hall’s, were identified, and the tweets of these likely community members were then downloaded for data analysis. Results of the UCI team’s work will be published in the December issue of Psychological Methods, a peer-reviewed academic journal of the American Psychological Association.

“Twitter’s rapid distribution and widespread use enable us to avoid the fundamental difficulties with traditional survey methodologies,” said Roxane Cohen Silver, professor of psychology & social behavior and research team leader. “Studying communities impacted by traumatic events is often costly and requires swift action to enter the field when disaster strikes. And individuals are typically studied after the traumatic event, so there’s no baseline data against which to compare post-disaster response.”

Social media such as Twitter offer a wealth of information that can provide an immediate window into a community’s emotional response to a collective trauma, but using a big data approach presents its own unique challenges, according to Nickolas M. Jones, lead author and graduate student in psychology & social behavior.

“Locating community members who have experienced the trauma can be problematic,” he explained. “To infer members’ location, prior researchers have either used geotagged tweets, which account for only 3 to 6 percent of Twitter users, or tweets with hashtags, which yields vast numbers of tweets without certainty of the users’ location. It’s critical for researchers interested in using big data to study how trauma affects a community to identify Twitter users who likely live there, and our method helps achieve that goal.”

The UCI team compared negative emotional expression via Twitter by people in the impacted communities and those in three matched control communities shortly before and after the campus killings. Despite variation in the severity of violence at the colleges, results showed similar patterns of increased negative emotional expression in the post-event tweets from those in the affected areas, while tweets from those in the matched control locales exhibited no change in negative emotional expression during the same period of time.

Based on the findings, the researchers believe Twitter is a creative tool that can be utilized to gauge negative emotion in the aftermath of violence, especially on college campuses, since students are the most likely users within the general population.

Josiah Sweeting, a psychology & social behavior graduate student, and Sean Wojcik, a former UCI doctoral student who’s now a senior data scientist at Upworthy, also contributed to the work.

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