Crowds going to open air markets versus a state leader who must lecture his compatriots: in France, not everyone is following the government’s order for general confinement.

Too many people take self-isolation “lightly”, French President Emmanuel Macron estimated this week, after he asked the French on Monday to stay at home as much as possible in order to fight the spread of the virus.

Before the measures were announced on Monday, photos of crowds relaxing in the sun in Parisian parks the previous weekend had gone viral on social media – the sign that many in Paris had not applied the government’s “social distancing” advice.

Elsewhere in Europe, German authorities are reluctant to move to forced lockdown, while many Germans, often young people, continue to ignore official calls to stay at home.

Even Italy, the first European country to have imposed strict and generalised measures, struggled imposing a total lockdown, AFP reported.

Increasingly, European countries hit by the coronavirus pandemic seem split in two, between those who quarantine themselves for the sake of the common good, and those who are reluctant to follow self-isolation measures.

But many people are not set on one or the other choice – rather, they make a decision based on what the majority does, Angela Sutan, a professor of behavioural economics at the Burgundy School of Business in France, told the AFP. Those who enjoyed sunny parks last weekend are part of this “malleable” margin.

“The problem is that these people are both the most important and the most dangerous,” Sutan said. “If they perceive that the others do not cooperate, they no longer cooperate”.

These conclusions are based on research in behavioral economics. This discipline, at crossroads between economics and psychology, seeks in particular to explain why irrational behaviours emerge from a pure economic point of view.

Austrian Ernst Fehr is a famous researcher in the field. In the early 2000s, he conducted a study that showed how attitudes are shared, based on a small panel:

A quarter of the sample contributes to the general interest no matter what
Another quarter think only of themselves
There remains a whole half, the famous “conditional contributors”, who are waiting to see how the majority behaves.
Social pressure helps
In this context, social networks “tend to show too many bad examples, which gives the impression that there are only stowaways”, Angela Sutan said. “It creates a vicious circle”.

But they can also have a beneficial effect, by allowing the dissatisfied to express broadly shared social disapproval, which will push the most selfish to review the costs and the benefits of their attitude.

“They feel like they are making a profit by going to the park because they have done an act of bravery,” Sutan explained. But if people are “met with disapproval on social networks”, they may reconsider.

What, then, is the best tactic for the authorities to convince people to self-isolate?

France and Italy have chose to enforce thousands of fines: anyone who’s found by the police to be outside when they shouldn’t gets one. Is this the best strategy, or is it wiser to play on the responsibility of citizens – which Macron also tried in one of his speeches?

A mix of both, according to several economists, who said asking the French to fill themselves a declaration on honor to justify exceptional trips is a positive strategy.

“When you put your signature on paper, there is a mental reflex which means that people, if they already had a tendency to respect the rules, want to respect the commitment made”, said neuroeconomics researcher and Sciences-Po professor Thierry Aimar.

“This signature will create mental mechanisms which will consist in respecting the commitment to avoid a form of cognitive dissonance”, he added.

“By the information economy, in most people who were already respectful of social norms, the brain will strengthen self-discipline”.

The effect risk dissolving in the long term, depending on what everyone else does. “If opportunistic behaviours develop, the attitude of people who are naturally respectful of injunctions risks evolving in the wrong direction,” concluded Aimar.

As four European countries are already under lockdown, and more to follow on other continents, the respect of such restraining measures remains one of the most effective way to slow down the rapid spread of the virus, according to the World Health Organization.