To Encourage Social Good, Walk the Walk

Professor Bryan Bollinger studies credibility

October 24, 2018
Entrepreneurship, Social Entrepreneurship
Professor Bryan Bollinger studied solar panel adoption patterns

If there’s an unusual behavior that benefits society, the best promoters are the ones who have invested in doing it themselves, according to new research from Duke University’s Fuqua School of Business.

Professor Bryan Bollinger studied efforts to promote residential solar power and found that campaigns that had ambassadors who had adopted solar themselves were more successful than when the ambassador did not adopt.

“It’s definitely a ‘walk the walk’ kind of situation,” Bollinger said. “The ambassadors’ decision to install solar themselves was a main factor in explaining campaign success.”

Bollinger’s work, funded in part by the U.S. Department of Energy, had already spawned a 27-page guide for communities seeking to boost local adoption of solar power. The book sets out the roles public, private and nonprofit entities play in boosting the adoption of solar energy and offers step-by-step instructions for setting up a local campaign.

Bollinger worked with Kenneth Gillingham, an economist at the Yale School of Forestry & Environmental Studies. The latest research also involved Gordon T. Kraft-Todd and David Rand of Yale University, and Stefan Lamp of the University of Toulouse Capitole. “Credibility-Enhancing Displays Promote the Provision of Non-Normative Public Goods” is newly published in the journal Nature.

Towns where the ambassadors who promoted the program adopted solar were much more likely to have successful solarize campaigns, as measured by the number of installations that were performed as part of the campaign.

“An alternative explanation for the positive correlation is that some campaigns might be more attractive than others, and that everyone, including the ambassadors, might be more likely to install in those campaigns,” Bollinger said. “But we were able to establish a causal relationship by leveraging differences in towns where, for example, we knew the ambassadors didn’t adopt solar only because their roof was not suitable. We still found a difference in the impact.”

Subsequent experimental studies verified that second order beliefs – our beliefs about what other people believe – were behind this effect.

 “People interpret the ambassador’s adoption decision as an indicator of his or her belief in the product and program,” Bollinger said. “If they find out that the ambassador is not a strong believer in solar, adoption by the ambassador will no longer lead to more adoptions.”

"(I)t increases the credibility if there’s some sort of cost in pursuing that action"

The researchers also found this kind of advocacy could work for other uncommon behaviors with social benefits, such as buying carbon offsets for flights, using recycled products, having a no-grass lawn and wearing a facemask in public when sick.

“While it increases the credibility if there’s some sort of cost in pursuing that action, that cost doesn’t have to be financial,” Bollinger said. “People might look at you funny when you wear a facemask, so there is a social cost.”

That there is some type of cost, however, is key.

“Promoting an activity without a cost this way would likely not have the same impact,” he said. “If you were to give a special deal to the ambassadors, and if people were aware of that, the ambassador’s adoption decision would affect others less. As you lower the cost of doing the action, it’s less of a signal of what your beliefs are.”

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