Will couples divide? Math may tell

By Julia Sommerfeld
Seattle Times staff reporter

	John Gottman
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Romantic love is often described with metaphors borrowed from science. We talk of sexual chemistry and Mars and Venus. Unlikely lovers are explained by the rules of physics — opposites attract.

Now a leading marriage expert and group of mathematicians say it all comes down to math, calculus to be precise.

The team, led by Seattle psychologist John Gottman, presented its mathematical formula for marital bliss yesterday at the annual meeting of the American Association for the Advancement of Science, in Seattle.

By hammering out equations based on how a couple interacts when arguing, Gottman said, he can predict with 94 percent accuracy which marriages will last and which will end in divorce.

This isn't just some parlor trick, Gottman said. "The math model gave us a scientific theory for understanding relationships."

The formula — based on observations of 700 couples over 14 years — is said to detect the long-term stability of a constantly bickering couple that defies even the nosiest neighbors' prediction of divorce. And the "perfect" marriage that unravels to everyone's surprise can't fool the calculator, Gottman said.

"At first, I thought it was ridiculous to try to translate something as ethereal as a human relationship into numbers," said Kristin Swanson, an applied mathematician at the University of Washington who helped develop the equation. "But I really can't quibble with over 90 percent accuracy."

Susan Heitler, a Denver marriage therapist and author of "The Power of Two," thinks the results suggest it's about time for psychology majors to learn a little math. "How couples interact isn't random; it's not surprising they would fall along predicable patterns that math could pinpoint," she said.

At his "love lab" at the Relationship Research Institute, Gottman demonstrated his methods on volunteers Andrea Rodgers and Michael Harris, who are set to wed this Fourth of July. The couple's shared euphoria at finding each other provokes the twin reactions "What a cute couple!" and "Can I puke now?"

At the demonstration, the poster couple for Valentine's Day is shut in a room and told to discuss an area of disagreement for 15 minutes while they're videotaped. It takes them awhile to figure out an area in which they aren't in perfect harmony, but they eventually decide on money and time management. They hardly come to blows over the issues — they laugh a lot and are sure to reconfirm that the other is just about perfect.
 
Technicians code their videotaped interaction, assigning points to the pair's emotional signals. A subtle but scornful roll of the eyes earns a negative four, a nod of interest receives a positive two, and a good-natured joke gets another positive two.

The math itself is a pair of differential equations, alphabet soup to the untrained eye.

James Murray, a professor emeritus at UW and Oxford University who helped concoct the formula, usually applies his mathematical theories to phenomena such as the spread of tumors and wolf populations.

His calculus transforms the stream of emotion codes into what the researchers call the "Dow Jones industrial average" of a relationship. A line graph that looks like the stock market in the late 1990s portends marital bliss. A marriage headed for divorce court looks more like the dot-com bust.

On the simplest of terms, couples with a ratio of five positive emotions to every one negative emotion are seen as destined for success. Those with about as many negative scores as positive are headed for trouble, Gottman said.

The next step in his research, he said, is to use the graphical information to develop targeted relationship therapies.

The formula reveals no surprises about Harris and Rodgers. Gottman scanned their computer printout, then offered the suddenly anxious couple his prognosis: "Happily ever after."

They showed four times more positive signs than negative.

"We've got scientific proof of what we've felt all along," Rodgers beamed.

Julia Sommerfeld: 206-464-2708 or jsommerfeld@seattletimes.com

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