When cities are in good moods, their inhabitants take more risks

Nov. 29 (UPI) -- Cities have moods, according to new research, and when a city's mood is on the upswing, the city's inhabitants tend to take more risks.

What determines a city's mood? Researchers used Twitter to find out. Their findings suggest a surprise sunny day or a win by a local sports team can engender positive feelings among people in the city.

Researchers analyzed the "sentiment" of millions of tweets geotagged in six different U.S. cities -- New York, Boston, Chicago, Dallas-Fort Worth, San Francisco Bay Area and Los Angeles -- to determine the fluctuating moods in different urban centers.

"We have found that Twitter users serve as the 'canaries' of their communities," Johannes Eichstaedt, a computational social scientist at the University of Pennsylvania, said in a news release. "What they say on Twitter is representative of the mood shared on the streets and in the local communities. So, using artificial intelligence, we were able to extract information about the mood of the community as a whole from what those on Twitter say."

Researchers were able to draw connections between mood upswings and unexpected positive events -- an overtime win by the local basketball team, for example, or an unexpected sunny day after several days of rain.

Finally, Eichstaedt and his colleagues worked to identify how a city's good mood impacts the behavior of its inhabitants.

Previous studies have shown people are more likely to take risks after a surprise positive event. An improved mood can cause people to feel lucky.

When researchers compared daily lottery ticket sales with a city's mood swings, they found ticket sales increased on days when sentiments on Twitter suggested an improved mood.

Eichstaedt and his fellow researchers published the results of their study this week in the journal PLOS One.

"By using social media data we were able to examine the impact of collective events upon subjective well-being at the scale of large cities," said Ross Otto, an assistant professor in the psychology department at the University of McGill. "This information about how fleeting city moods are tied in with risk-taking behavior could potentially help those who want to discourage others from gambling decide when their responsible gambling promotion efforts will be most needed."