Want people to give? Tell them the last few people in a row did. Across 11 experiments, inviting people to join a short, ongoing streak of donors raised giving more than telling them that a large share of people had donated.
The study is by David E. Levari and Michael I. Norton. It appears in the September 2026 issue of the Journal of Experimental Social Psychology.
A streak instead of a statistic
Charities often use social norms, such as “X% of people have done it,” to nudge behaviour. The authors tested a different message built on collective streaks: “the last X people in a row have done it.” Their 11 experiments involved 12,688 participants in total.
Streak messages outperformed percentage messages even when the streak was short and the percentage was high. The authors trace the effect to a feeling of personal impact: being asked to extend a streak made people feel their own donation would influence the donors who came after them.
Works even for unpopular causes
The streaks worked even when the people in them were anonymous. And they offer a way around a weakness of percentage norms, which only help when a behaviour is already common. The authors give a stark contrast: saying 5% of people have donated is far from motivating, while saying 5 people in a row have donated prompts further giving.
The broader lesson, in the authors’ view, is that learning about the behaviour of just a few peers can be a powerful motivator, especially when it lets people see themselves shaping what others do next.
Study Details:
- Title: Collective streaks motivate prosocial behavior
- Authors: David E. Levari, Michael I. Norton
- Journal: Journal of Experimental Social Psychology
- Publication Date: September 2026
- DOI: 10.1016/j.jesp.2026.104941