Smoking and the hive mentality

Researchers have found that smoking cessation works best when you concentrate on groups.

The New York Times reports:

The study, by Dr. Nicholas Christakis of Harvard Medical School and James Fowler of the University of California, San Diego, followed thousands of smokers and nonsmokers for 32 years, from 1971 until 2003, studying them as part of a large network of relatives, co-workers, neighbors, friends and friends of friends.

It was a time when the percentage of adult smokers in the United States fell to 21 percent from 45 percent. As the investigators watched the smokers and their social networks, they saw what they said was a striking effect — smokers had formed little social clusters and, as the years went by, entire clusters of smokers were stopping en masse. So were clusters of clusters that were only loosely connected.

Dr. Christakis described watching the vanishing clusters as like lying on your back in a field, looking up at stars that were burning out. “It’s not like one little star turning off at a time,” he said. “Whole constellations are blinking off at once.”

As cluster after cluster of smokers disappeared, those that remained were pushed to the margins of society, isolated, with fewer friends, fewer social connections.
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The new study also looked at smoking initiation but, because many more adults were stopping smoking than starting in the years of the study, its main focus was on cessation. Still, Dr. Christakis said, smoking initiation followed the same patterns as cessation: people started and stopped smoking in groups.
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The study and the obesity study that preceded it, said Duncan Watts, principal research scientist at Yahoo! Research in New York, provide a new view of society.

“We tend to think of individuals as atomized units, and we think of policies as good or bad for individuals,” Dr. Watts said. “This reminds us that we are all connected to each other, and when we do something to one person, there are spillover effects.”

Traditionally, economists think of individuals as atomized units. It is not immediately apparent to me that economists will need to abandon that tenet to explain these facts. Some relationships are part of our environment, taken as given just as we take larger economic conditions as given when we make individual decisions. Other relationships are choices. Thus, if an individual wants to quit smoking he knows that changing his circle of friends will make a difference -- that is, if nonsmokers will admit him. Or he knows that making a pact with friends to all quit smoking together can make a difference.