The Power of Small Changes

IN THINKING HOW TO SOLVE some of our biggest global problems — issues like poverty, malnutrition and climate change — a good place to start is by identifying some of the small changes that could yield big improvements.

This is not a new principle. In 1961, MIT meteorologist Edward Lorenz constructed a mathematical model containing a set of 12 differential equations to predict weather patterns. One day, he wanted to re-examine a sequence of data and, to save time, he manually entered data from a printout of the previous run in the model. To his amazement, the results from the second run were dramatically different from the results of the first.

Upon further examination, he realized that he had entered the data to three decimal points — whereas the previous run had used the same data, but to six decimal points. This tiny difference in initial conditions had produced completely different results. These observations ultimately led him to formulate what we now call ‘The Butterfly Effect’, a term derived from an academic paper he presented in 1972: “Predictability: Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?”

The Butterfly Effect has since been used to explain numerous major changes in society. In The Tipping Point, Malcolm Gladwell describes how William Bratton — first as head of the New York Transit Authority’s police force (1990-1994) and then as head of the NYPD (1994-1996) — dramatically reduced crime in the city by implementing a few (seemingly) minor changes, such as cracking down onfare-dodging on the subway and penalizing quality-of-life crimes, like public drunkenness and public urination.
Similarly, in their best-selling book Nudge, professors Richard Thaler and Cass Sunstein describe several examples where small changes have produced radical results. For example, by painting a life-sized image of a black housefly on each urinal, authorities at Amsterdam’s Schiphol Airport reduced ‘spillage’ in men’s washrooms by 80 per cent.
Elsewhere, officials in Minnesota achieved a significant increase in tax compliance, simply by telling people that more than 90 per cent of Minnesotans already complied in full with their obligations; and in Texas, authorities achieved a 29 per cent reduction in roadside littering within a year of launching the ‘Don’t Mess with Texas’ advertising campaign.

Equally impressive examples of the Butterfly Effect have been provided by social psychologists. In one study, asking people to donate blood by having a friendly peer comply with the request was found to increase the success rate from 25 per cent to 67 per cent. More importantly, none of the subjects in the no-model experiment followed up to actually give blood, whereas 33 per cent of the subjects in the model experiment did so.

Similarly, simply commending children for already being very clean and tidy was found to increase their tidiness by a factor of four in the short term — a behaviour that remained unchanged long after the experiment was completed. Meanwhile, children who were told to be more tidy increased their tidiness in the short term by a factor of two — but reverted to their pre-test level of littering after the experiment. Children who were neither told to be more tidy nor praised for being tidy did not change their behaviour.
There are also examples from the world of business. In one study, workers in a pyjama factory were asked to take on board a seemingly small change in the way the pyjamas were sewn or boxed. One group of workers was simply informed of the change. In another group, a selected team of workers was asked to meet with manage