But The Times recently ran a piece that is also near and dear to my heart — emphasizing the power of peer pressure to change behavior. Positive Energy has been working with the Sacramento Municipal Utility District to test the impact of giving customers a different kind of information on their energy bill:

Last April, it began sending out statements to 35,000 randomly selected customers, rating them on their energy use compared with that of neighbors in 100 homes of similar size that used the same heating fuel. The customers were also compared with the 20 neighbors who were especially efficient in saving energy.

Customers who scored high earned two smiley faces on their statements. “Good” conservation got a single smiley face. Customers … in the “below average” category got frowns, but the utility stopped using them after a few customers got upset.

The exciting news is that “customers who received the personalized report reduced energy use by 2 percent more than those who got standard statements.”

This isn’t a surprise to Robert Cialdini (the author of the classic book Influence), who back in 2004 published a small, randomized study of 290 households in San Marcos, California — again looking at the impact of emoticons (those smiley and frowny faces) on energy consumption. The following figure summarizes the core results:

Peer information alone led to a reversion to the mean. The households that consumed above the average reduced their consumption, while the below-average households responded to the good news that they were consuming less by increasing their energy consumption. But look what happens in the right-hand columns where peer information is paired with the emoticons. The above-average energy consumers again conserved, without the perverse energy increases from the households that started below average. It looks as if these conserving households act to keep their gold star of approval.

There is also a great writeup of this study as a prime example of choice architecture in the book Nudge. The independent power of the emoticons shows that what’s going on is not just the dissemination of information; it’s about how the information is framed.

In Sacramento, Positive Energy ultimately discontinued sending out the emoticons after a few complaints. But an intermediate strategy would be to discontinue the frowny faces to the energy hogs but continue sending out smiley faces to the “good” conservationist households.

I should add that Cialdini has a financial interest in these outcomes, as he owns a stake in Positive Energy. I also have more than a passing interest. I’m working with Positive Energy to analyze future data on the power of both peer information and commitment contracts. I’ve also been promoting the value of peer information for the last few years. Back in 2005, Barry Nalebuff and I published an article in Forbes, arguing for something right in line with Positive Energy’s core mission:

Why not have the heating bill tell you if you’re using too much energy? Most heating bills report how much gas or electricity you used last month compared with a year ago. A lot of them also report heating degree days (how far and how long the temperature veered below 65 degrees over the course of the month). But this pair of numbers isn’t very helpful. Together they don’t tell you whether you need to upgrade your insulation.

There’s a better way to answer this question. Just tell people how much energy they used that month compared with other people in similar-size homes. In many cities (including our own New Haven), the square footage of each house is publicly available — so the gas company could calculate the energy per square foot for each house and display the information on each month’s bill. Further helping you out by doing the math, it could report energy consumed (in BTU) per square foot per degree day.

We’ll call this measure B-Tush (BTU per square foot per heating degree day). The key here is to report how folks did relative to their neighbors. According to a 1997 Department of Energy survey, the U.S. average B-Tush is 10. If you are up to 25, then you are among the worst 10 percent. You should invest in better insulation — or else turn down the thermostat and buy some sweaters.

Economists tend to think of information and incentives as the core drivers of human behavior. But Cialdini and Positive Energy have me thinking that smiley faces may also play a useful role.

P.S. stickK.com hasn’t quite gone so far as to include emoticons in its messaging to help people stick to their commitments, but we are enhancing the behavioral support features. We’ve just launched several new communities (concerning things like “health and lifestyle,” “green initiatives,” and “money and finance”) to help people better connect with others who have similar goals.