Comparing Groups Motivates Behavior

Ferguson, Mark A., Branscombe, Nyla R., & Reynolds, Katherine J. (2011). The effect of intergroup comparison on willingness to perform sustainable behavior. Journal of Environmental Psychology, 31, 275-281.

Research has shown that comparing people to others in their same group--called intragroup comparisons--can motivate engagement in sustainable behavior. For example, in a recent study, researchers told hotel guests that former occupants of the same room had conserved water by not sending towels to be washed daily. This comparison with guests in the same room served as an intragroup comparison, and it influenced the current occupants' towel use, causing them to also cut back on towel washing.

The research in this article focused on another aspect of social comparison, specifically whether intergroup comparisons, in which individuals compare their group to an outside group, can promote sustainable behavior. The authors explain that research has indicated that when members of one group (called the ingroup) perceive their group as different from another group (called the outgroup), they will “distance themselves from outgroup norms, to enhance their ingroup's distinctiveness relative to the outgroup.” The researchers sought to determine whether this dynamic exists with sustainable behavior.

In this study, two experiments were conducted in which university students compared themselves with either a past or future generation and then reported their willingness to perform sustainable behavior. In the first experiment, 55 undergraduate psychology students completed an online survey for course credit. The survey either indicated that it was designed to help researchers understand the opinions of students in 1960 and 2010 or it said the survey would help them understand the opinions of students in 2010 and 2060. Half the students were assigned to each survey, in which they would compare their generation (in 2010) to either the past generation or the future generation. The students were asked to think about the important differences between their generation and the other generation before beginning the survey. They were then given a short passage to read about our current knowledge about climate change. After reading the information, the students completed questions about their willingness to engage in sustainable behaviors in the areas of transportation choices, energy and water conservation, and social advocacy.

The second experiment was much the same, except it added two new dimensions. First, the researchers also asked the students about their beliefs about climate change, in order to understand if the students' beliefs explained their behaviors. The second experiment also added support for environmental policies, and asked students about their support for taxes and regulations to help limit greenhouse gas emissions.

In both experiments, current students who compared themselves to the past generation reported more willingness to perform sustainable behaviors than the students who compared themselves to a future generation. The authors explain, “The comparative context provided a frame of reference for interpreting current students' norms as more sustainable by comparison with a past generation, but less sustainable by comparison with a future generation.”

In experiment two, the students who compared themselves to students of the 1960s also reported greater support for taxes and regulations to limit greenhouse gas emissions. And the second experiment also revealed that the group that compared themselves to the past generation held more sustainable beliefs regarding climate change, and that these beliefs fully explained their willingness to participate in social advocacy, and support taxes and regulations. The beliefs partially explained their willingness to conserve energy and water, but they didn't explain their transportation choices. The researchers suggest that other psychological factors are needed to understand energy-conservation and transportation.

In conclusion, the researchers think this study suggests an important strategy for effectively motivating people to engage in more sustainable behaviors. By comparing an ingroup to a less sustainable other group, the ingroup will think of themselves as more sustainable. “Accordingly,” the authors explain, “inducing intergroup comparisons that portray the ingroup as more sustainable relative to the outgroups could be useful for promoting sustainable beliefs, values, and behaviors, as they offer opportunities for ingroup members to affirm their distinctiveness from other groups.”

The Bottom Line

When communicating about desired environmental behaviors, portraying the audience's group as more sustainable than other groups can lead the audience to shift their beliefs and intentions to act in ways that affirm their group's identity. In environmental education programs, educators could draw comparisons between their students and other groups to highlight differences where their students are more sustainable. But it's important to note that this study used only people's self-reported intentions to act, so it's not known how the comparisons affect actual behavior. And this study focused only on university students, so further research is needed to confirm the effectiveness of this approach with other audiences.