USC professor measures political polarization


The ten issues measured by “The Polarization Index” and the degree of discord between the left and right on each. Immigration, policing policy and abortion saw the most activity. (Image Courtesy of The Polarization Index website)

From a quiet office shaded by trees in the Annenberg School for Communication and Journalism, USC professor Fred Cook is one of the only people in the world putting numbers to the most pressing issues in American politics. 

Last March, Cook released “The Polarization Index,” a first-of-its-kind political report that quantitatively measures polarization on 10 major legislative issues in the United States. 

Cook created the report in collaboration with Golin, a PR firm and narrative intelligence company Zignal Labs. Spanning a variety of political issues, the report explains which political party is most engaged, how divided Democrats and Republicans are on a topic and the relative amount of unreliable information being circulated through social media. 

“We became really interested in polarization before [President Trump] left office,” Cook said. “I was interested to see if the level of activism on both sides would be reduced or increased after the change [in administration].”

To add a qualitative measure to “The Polarization Index,” Cook and his collaborators tracked Twitter engagement with pieces of media from 450 news outlets, which had previously been ranked by reliability. When a user retweeted a piece of media, the topic that it discussed was ranked as more or less polarized based on the reliability of the content. The more unreliable content that was shared on a topic, the more polarized the topic was considered.

“The Polarization Index” was originally created to help guide corporations through tense political times where more consumers expect their employers and producers to take a stand on social issues. However, the index also has the potential to reveal more nuances about the state of U.S. politics, especially ahead of the upcoming midterm elections.

The results of the first edition of the study revealed new revelations about what the political parties prioritized: Democrats and Republicans were found to be focused on completely separate issues. Republicans tended to devote significantly more time to discussing immigration and crime, while Democrats were more focused on abortion and the Jan. 6 investigation. There was little overlap between the two.

“Polarization isn’t a result of people disagreeing,” Cook said. “It is the cause of people disagreeing, and it’s becoming a strategy that politicians and media use to build their audience.”

In Cook’s opinion, Florida Gov. Ron DeSantis’s recent decision to fly undocumented immigrants to Martha’s Vineyard was a perfect example of intentional actions taken to polarize the public by political officials. 

“He knows immigration is what’s gonna power his brand and excite his people,” Cook said. “So he creates this story … and immigration is back in the news because he put it there.” 

Cook believes such polarizing stunts work best with issues such as immigration, because it was “not the most talked about issue on our list, but the most polarizing because the difference of opinion is greater and the media sources that are talking about it are less reliable.”

USC students reacted to the study’s results with both apprehension and appreciation. 

“It’s scary to see how polarized these key issues are,” said John Belton, a sophomore studying public policy. “In a time when bipartisan solutions are needed, it’s clear that it is becoming harder and harder [to accomplish] as the nation becomes more divided. It’s impressive to see the work that went into the quantification of polarization, and I can hope that by being aware of this trend, I can help solve the problem.” 

Cat Cornish, a junior majoring in public relations and political science, thought that the best aspect of “The Polarization Index” was that it recognized an issue within the public relations industry that people are aware of but few know how to address. 

“I’d be super interested to see if they ever track [polarization] on Facebook, because I know the dialogue on Facebook is wildly different than it is on Twitter,” Cornish said.

Despite the discord, Professor Cook believes that there is a way out of polarization in the next few years. 

“We need to work together,” Cook said. “USC students have to be aware that they’re being manipulated by people who are in the media and in politics.”