Social norms

Social-norms interventions communicate what other people in a relevant comparison group are doing. The classic form is a letter or message that says, in effect, 'most people in your situation pay on time / vaccinate / conserve energy.' The mechanism is descriptive: receivers update their sense of what is normal, and adjust their own behavior toward the norm.

5

Experiments

3

Policy areas

2006–2019

Year span

5 / 5

Positive

When it works

When the actual behavior in the comparison group is more compliant than the recipient assumes, and when the comparison group is genuinely meaningful (your neighborhood, not 'all Americans'). Most reliable for low-effort, frequently-performed behaviors where conformity is socially cheap.

Watch out for

Backfire effects: if the recipient is already above average, learning that 'most people' do less may pull them down toward the mean. Always include a sanction-of-approval cue (a smiley face, a positive frame) for the above-average cohort. Also: norm messages that don't match reality erode credibility quickly.