Research suggests social media ‘likes’ can amplify moral outrage

13 Aug 2021

Image: © Samuel B./

Yale researchers looking at online behaviour found that social media sites ‘create incentives that change how users react to political events’.

Leaving an indignant comment on Facebook or tweeting an angry response might feel cathartic, but what is the impact of these messages of moral outrage? New research from Yale has found that they might be spurring people on.

In a study published today (13 August) in the journal Science Advances, researchers used machine learning to measure moral outrage on Twitter while controversial events were occurring. They also studied the behaviour of participants in controlled experiments that aimed to see how social media algorithms might encourage outraged opinions.

“Social media’s incentives are changing the tone of our political conversations online,” said Yale’s William Brady, a postdoctoral researcher in the university’s Department of Psychology and first author of the study. He led the research with Molly Crockett, an associate professor of psychology at Yale.

“This is the first evidence that some people learn to express more outrage over time because they are rewarded by the basic design of social media.”

How social media could affect us

Brady and Crockett were interested in the nature of platforms like Facebook and Twitter. Do they simply provide a stage for people to express their views or is there a more complex cycle of factors at play? Could these systems be amplifying moral outrage?

There was no existing technical evidence of this, as quantifying and measuring complex social expressions such as moral outrage poses a technical challenge, the researchers said.

They suspected reinforcement and norm learning could be two mechanisms through which outraged expressions might increase. Likes and shares on outraged posts would increase the incentive to make similar posts in the future, while seeing others expressing these opinions would create a status quo to be followed.

To gather evidence, Brady and Crockett assembled a team to build machine learning software that was able to track instances of moral outrage on Twitter posts. This was key to the researchers’ goal of working with real-world samples. Events such as a United Airlines passenger being forcibly removed from a plane were chosen, with a total of 12.7m tweets being analysed from 7,331 users.

Researchers examined whether users expressed more outrage over time, and found that users who received more likes and retweets were more likely to express outrage in future posts.

‘Amplification of moral outrage is a clear consequence of social media’s business model, which optimises for user engagement’

The researchers also carried out controlled behavioural experiments with 240 participants that showed being rewarded for expressing outrage caused users to express more outrage over time.

“Our studies find that people with politically moderate friends and followers are more sensitive to social feedback that reinforces their outrage expressions,” Crockett said.

“This suggests a mechanism for how moderate groups can become politically radicalised over time – the rewards of social media create positive feedback loops that exacerbate outrage.”

How society copes with moral outrage

Crockett highlighted that the study did not intend to say whether amplifying moral outrage is good or bad for society, but it did suggest possible implications for leaders who use the platforms.

“Amplification of moral outrage is a clear consequence of social media’s business model, which optimises for user engagement,” Crockett said.

“Given that moral outrage plays a crucial role in social and political change, we should be aware that tech companies, through the design of their platforms, have the ability to influence the success or failure of collective movements.

“Our data show that social media platforms do not merely reflect what is happening in society. Platforms create incentives that change how users react to political events over time.”

Sam Cox was a journalist at Silicon Republic covering sci-tech news