On the Dynamics of Sustainable Behaviours

On the Dynamics of Sustainable Behaviour

Our Senior Research Fellow, Dr Raisa Sherif, investigates in a field study in India the effects of environmentally friendly behaviour which leads to some remarkable finds.

Ocean Pollution, heat, heavy rain and floods: The negative impacts of climate change and environmental degradation are visible and tangible worldwide. Many governments are now not only committed to reducing CO₂ emissions, but are also using targeted measures to stop the pollution that is threatening our ecosystems. One way is to promote environmentally friendly behaviour through new policies and regulations. For example, the European Union is banning certain single-use plastics to reduce waste and protect the environment.

That such a ban will reduce the use of single-use plastics in the long run is obvious. However, what is unclear and largely unexplored is the wider impact of such measures on individual behaviour. This is what Dr Raisa Sherif aims to discover with her research paper “Are Pro-environment Behaviours Substitutes or Complements? Evidence from the Field”. She investigates whether people who comply with such regulations feel they are already sufficiently committed to environmental protection or whether the establishment of such sustainable behaviours creates positive feedback effects that motivate them to behave in an environmentally friendly manner in other areas of their lives as well.

A field experiment in India

To get to the bottom of her research question and to find out how young people develop in an environment where environmentally friendly measures are established and specifically promoted, Raisa Sherif conducts a field experiment in her home country, India. In cooperation with the Green Kerala Mission  of the government of the Indian state of Kerala, she sets up recycling centres for single-use plastic bags for more than 3,750 students in 120 classrooms. They then implement two interventions to increase recycling rates. The first is an information campaign that educates students about the environmental consequences of the improper disposal of single-use plastic and the importance of recycling. The second combines this information with incentives for recycling, i.e. students who actively participate receive certificates from the district administration in recognition of their outstanding efforts. They are also invited to an event called “Tea with a Movie Star” where these certificates are presented.

The study shows that the initial interest in recycling is very low among all pupils and that the information measure does not change their recycling behaviour significantly. However, the incentive treatment leads to a significant increase in the participants’ recycling efforts.

Measuring further impacts and possible feedback effects of the two interventions presents a noticeable challenge, as it is almost impossible to observe all the environmentally friendly behaviours that students subsequently engage in. Surveys are also not very suitable for obtaining reliable data. Research shows that students often give too much information because they want to appear more environmentally friendly than they actually are.

Spillover effects under the microscope

To verify the effects of the two interventions on the participants, laboratories are used. Raisa Sherif collects data on students’ willingness to pay (WTP) for seven different environmental activities before and after the interventions. These activities include paper recycling and tree planting. The students’ contributions to the chosen activity are subtracted from their experimental gains. Positive side effects are noticed if students are willing to pay more for environmental activities after the first or second intervention than before.

The data collected in the labs clearly show that the incentive treatment, i.e. the second intervention, had a positive effect on the students’ behaviour: The incentive treatment, which aimed to increase the recycling of single-use plastic bags, not only changed recycling behaviour, but also increased students’ willingness to pay for other environmental activities, revealing the complementarity between them.

Interestingly, the side effects are not limited to students who increased their recycling efforts. Students who did not change their recycling behaviour but were confronted with the issue through the recycling efforts of their peers also showed positive side effects. This means that the intervention had positive side effects on non-targeted, environmentally friendly behaviours – even if it did not directly affect the target behaviour!

Targeting sustainable behaviours

These findings suggest that the positive effects of targeted sustainable interventions are still underestimated. Translating the research findings into everyday life, it is conceivable that people who are asked to give up single-use plastic will consequently act in a more environmentally friendly way in other areas as well and, for example, choose to shop with less packaging. Furthermore, Dr. Raisa Sherif’s findings suggest that carefully designed policy measures can provide opportunities for action and help raise awareness of sustainable behaviour, triggering cascading effects and accelerating the adoption of sustainable behaviours in our society.


Are Pro-environment Behaviours Substitutes or Complements? Evidence from the Field by Raisa Sherif :: SSRN

Picture: © PK3 field team



October 2023