Tip the balance

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For years, social scientists have theorised that changes in social norms can occur because of small but committed groups of people pushing for change, and that established conventions can be overturned when a critical mass of opinion is reached – the tipping point – leading to social change.

The exact stage at which tipping happens has been debated. In standard economic theory, equilibrium stability analysis suggests that a group will only change if 51% of its population initiate the change, while other studies have suggested 10% of people in a group could be enough to shake it up. In a world where ideas can spread faster than ever via social media, the ability of activist movements – such as Black Lives Matter and #MeToo – to propagate social change has taken on new significance. 

While the argument for tipping points is persuasive, however, there has previously been no empirical evidence to prove their existence, or to quantify the critical level for social change. Does a group really need half of its members to advocate for new norms, or can conventions be overturned by a vocal 10%? Is it even possible to measure?

“Mathematicians and physicists have spent decades building theories that try to predict where the ‘tipping point’ for social change might be,” says Damon Centola, a researcher from the University of Pennsylvania, who has studied the subject for the past 10 years. “While there have been dozens of theories, none of them have been empirically tested – so while the tipping point is a provocative idea, there has never been concrete evidence that it exists.”

Change dynamics

The biggest challenge of studying critical-mass dynamics, Centola explains, is that – to understand successful social-change efforts – these events would need to be studied side by side. “‘History’ only happens once. If an activist group fails, it is hard to know whether they would have succeeded if only they had been a little bigger – or, if they succeed, it is hard to know whether they might have failed if something had been different,” he says.

In a new study, Centola and co-researchers from the University of Pennsylvania and City, University of London, present evidence for tipping points by setting up an artificial system of social conventions, mimicking the social coordination processes and change dynamics that occur in everyday settings. 

The researchers recruited 194 participants via websites such as Reddit and sorted them into 10 online community groups, varying in size from 20 to 30 people. They were given the task of interacting with a randomly chosen partner with the aim of agreeing on a linguistic convention. They were shown a picture of a face and asked to come up with a name for the person pictured – for example, Sarah, Simone, Deirdre, and so on.

The naming happened simultaneously, with participants incentivised to match with their partner; if both partners selected the same name, they were rewarded financially, whereas failure to match would lead to both being penalised. If the partners failed to match, they were shown each other’s selections, so they learned about the choices others were making before moving on to interact with someone else – until a naming convention was agreed upon, and a social norm
was established. 

“We allowed people to circulate and interact with lots of different people, to see if a shared linguistic norm would emerge for the population as a whole. After a short period of time, everyone would converge on using a single name,” says Centola.

Committed minority

The researchers then introduced an activist group into each of the communities, which attempted to overthrow the agreed norm by promoting an alternative name convention. For instance, if the group had converged on ‘Sarah’, the activist would try to change the name to ‘Jasmine’. 

The ‘committed minorities’ ranged in size across the 10 groups – from 15% to 35% of a group’s population – but the tipping point that emerged across each of the studies was the same: roughly 25%. The finding not only cements the existence of tipping points, but suggests they could be identified within a social system, says Centola. 

The researchers were also able to see which groups were on the verge of tipping. In the clearest example of this, the minority went from a complete failure – with no converts – to converting the entire group by adding a single person to one of the activist groups. “A movement that appears to be failing may instead be right at the cusp of succeeding,” says Centola.

Dark side

The paper stresses that 25% is not a universal value for changing social norms and more work is needed within other social settings. However, Centola believes the results could be used to design online spaces where it is possible to initiate “useful social change” – because, just as critical-mass dynamics can lead to positive social change, there is a dark side to tipping points: they can be used by governments and organisations looking to exert control. 

The paper points to recent work by the 50 Cent Party in China, a group of internet commentators ostensibly employed by the government to infiltrate online communities anonymously to subtly influence dialogue, manipulating public opinion of the government. 

Centola is currently working on a new study examining whether commentators ever reach the tipping point of 25%. 

Understanding where tipping points occur could also be pertinent for the workplace. Once norms are solidified as an organisation’s ‘culture’, they are reinforced by all employees, but a small group of individuals could be enough to shift the dynamics of a large organisation – an enticing prospect for tackling toxic cultures. 

“Building on the idea that originally inspired me – that is, [Rosabeth Moss] Kanter’s idea that norms of sexism in corporations could be overturned if only a critical mass of women was reached – the good news from this study is that social norms are remarkably flexible,” says Centola. 

“Big changes that eliminate sexism from office culture can be achieved if only a few more people join the cause.”

Reference:

‘Experimental evidence for tipping points in social convention’, by Damon Centola, Joshua Becker, Devon Brackbill and Andrea Baronchelli, Science, 8 Jun 2018: Vol. 360, 
Issue 6393 

How Behavior Spreads: The Science of Complex Contagions, by Damon Centola, is published by Princeton Press.