The Effect of Social Norm Nudges on Littering in Dutch University Campus Buildings

Fostering a sense of belonging and a positive atmosphere in tertiary education impacts student motivation and persistence, with campus environments playing a crucial role. Littering can disrupt this experience, making it important to address. This study used a quantitative approach to examine the effects of social norm interventions on littering at a Dutch university campus. Conducted in two buildings, the experiment included daily litter measurements. One building received a social norm intervention using persuasive communication, while the other served as a control. Litter levels were measured at baseline, post-intervention and seven months later, analyzed using logistic regression. Trashcan presence was noted. Littering decreased significantly in the treatment building (63% vs. 23% post-intervention, 28% follow-up). The treatment effect was significant at post and follow-up measurements, showing short- and long-term behavior change. Trashcan proximity affected the intervention at follow-up. Social factors play a key role in reducing littering. Future research should explore the dynamics with physical disposal opportunities further.