New theory explains political polarization

Scientists at the CSH expand an old theory of balance to explain the emergence of hyperpolarization

A new model of opinion formation shows how the extent to which people like or dislike each other affects their political views —and vice versa. The resulting division of societies can even become a matter of life and death, as the current crises show.

The ever-deepening rift between the political left- and right-wing has long been puzzling theorists in political science and opinion dynamics. An international team led by researchers of the Complexity Science Hub Vienna (CSH) now offers an explanation: Their newly developed “Weighted Balance Theory” (WBT) model sees social emotions as a driving force of political opinion dynamics. The theory is published in the Journal of Artificial Societies and Social Simulation (JASSS).

A certain degree of polarization of political opinions is considered normal–and even beneficial–to the health of democracy. In the last few decades, however, conservative and liberal views have been drifting farther apart than ever, and at the same time have become more consistent. When too much polarization hampers a nation’s ability to combat threats such as the coronavirus pandemic, it can even be deadly.

How do extreme positions evolve?

“We feel high balance when dealing with someone we like and with whom we agree in all political issues,” explains first author Simon Schweighofer, who was a PostDoc at the Hub when the paper was written. “We also feel high balance towards those we hate and with whom we disagree,” adds the expert in quantitative social science. The human tendency to maintain emotional balance was first described 1946 by Fritz Heider’s “cognitive balance theory.”

But what happens when opinions and interpersonal attitudes are in conflict with each other, i.e., when individuals disagree with others they like, or agree with others they dislike? “People will try to overcome this imbalance by adapting their opinions, in order to increase balance with their emotions,” says Simon.

A vicious circle of increasingly intense emotions and opinions gradually replaces moderate positions until most issues are seen in the same—often extremely polarized—way as one’s political allies, the scientists found.

“It ultimately ends in total polarization,” illustrates co-author David Garcia (CSH, MedUni Vienna). Not only do people categorically favor or oppose single issues like abortion, same-sex marriage and nuclear energy. “If they are pro-choice, they are at the same time highly likely to be for gay marriage, against the use of nuclear energy, for the legalization of marijuana, and so on.” The possible variety of combinations of different opinions is reduced to black and white—the traditional left-right split.

A mathematical model of hyperpolarization

The researchers developed a so-called agent-based model to simulate this process. Their mathematical model was able to reproduce the same dynamics that can be observed in real-life political processes (see videos below).

“We call the combination of extremeness and correlation between policy issues hyperpolarization,“ says Simon. “Hyperpolarization has so far been overlooked in social theories on opinion formation. Our Weighted Balance Model—which is a truly interdisciplinary effort that integrates research strains from psychology, political science and opinion dynamics into an overarching theoretical framework—offers a new perspective on the emergence of political conflict,” he concludes.

The study, entitled “A Weighted Balance Model of Opinion Hyperpolarization”, will appear in print on 30 June 2020 in the Journal of Artificial Societies and Social Simulation.

Video 1:

Emergence of hyperpolarization

The simulation demonstrates the emergence of hyperpolarization, showing the link between social emotions and opinion divergence.

The three dimensions correspond to three political issues (e.g., marihuana legalization, gay marriage, or income taxation). The space spanned by these dimensions is the “opinion space.” Each blue dot represents an individual. From random positions, individuals rapidly converge in the middle of the opinion space (where all three issues are irrelevant). At the same time, they align themselves along a diagonal, corresponding to the political spectrum, i.e. from far left to center to far right. In the next step, they split into two groups, corresponding to political parties. Members of the same party now have identical opinions on all three issues, and opposing opinions to the other party. This conflict creates positive feelings towards one’s party colleagues and animosity towards the other party, driving the individuals ever further apart, until they are in opposite corners of the opinion space.

Video 2:

Opinion change and weighted balance

This simulation shows how individuals react to another individual according to his/her changing opinions.

As individual 1 [red arrow] moves in a circle through the opinion space, others [the black arrows] with already similar opinions (i.e. whose opinion vector is less than 90 degrees away from individual 1), and thus a positive relation towards the individual, move closer. Others who dislike the individual due to differing opinions move away. Repeated interaction leads to individuals either agreeing with on all issues, or adopting opposing views. The background color shows how much cognitive balance they perceive.