How to Get People to Pitch In

Erez Yoeli, Syon Bhanot, Gordon Kraft-Todd And David Rand in The New York Times: “…The “Pigouvian” approach to encouraging cooperation, named after the economist who first suggested it nearly a century ago, is to change the price — i.e., the personal cost of cooperating: Make water more expensive, tax carbon or pay people to vaccinate their kids.

But Californians are stubbornly unresponsive to higher water prices. Estimates suggest that a 10 percent increase in price would result in reductions in water use of 2 to 4 percent. That’s not nothing, but it implies that huge, politically infeasible price increases would be needed to address the state’s needs.

This problem isn’t unique to Californians and their effort to save water. In a recent review of field experiments that promote cooperation in the journal Current Opinion in Behavioral Sciences, we found that changing the material costs and benefits of cooperation often doesn’t work. Researchers have tried various forms of payments — paying cash, handing out T-shirts — and they’ve tried providing information on how to cooperate, with only limited success.

What does consistently work may be surprising: interventions based not on money, but on leveraging social concerns.

There are two ways to do this, both building on people’s desire for others to think highly of them. One is to make people’s cooperative (or selfish) choices more observable to others, like neighbors or co-workers. The second works in the opposite direction, providing people with information about how others around them are behaving (this is called a “descriptive social norm”).

To see how this might work, consider the California drought. The state could set up a website where homeowners pledge publicly to reduce their water consumption by 15 percent. Those who do would get a lawn sign that would say something like, “My lawn is yellow because I took a pledge to help California. Join me at”

And what about norms? Innovative companies and public utilities are already on the case. A San Francisco-based firm, WaterSmart Software, sends mailers that allow homeowners to compare their water use to their neighbors’. Estimates suggest that these mailers reduce water use by 2 to 5 percent — the same as a 10 percent price increase.

Why do social interventions work? Research on the evolution of cooperation provides an answer. Beyond helping our families — the people to whom we’re genetically related — making others better off is not our main motivation to give. Instead, we cooperate because it makes us look good. This can be going on consciously or, more often, subconsciously (a gut feeling of guilt when your neighbor sees you turning on your sprinkler).

When your choices are observable by others, it makes it possible for good actions to benefit your reputation. Similarly, norms make you feel you’re expected to cooperate in a given situation, and that people may think poorly of you if they learn you are not doing your part….(More)”