When thousands of poor families were given federal housing subsidies in the early 1990s to move out of impoverished neighborhoods, social scientists expected the experience of living in more prosperous communities would pay off in better jobs, higher incomes and more education.

That did not happen. But more than 10 years later, the families’ lives had improved in another way: They reported being much happier than a comparison group of poor families who were not offered subsidies to move, a finding that was published on Thursday in the journal Science.

And using the gold standard of social surveys — the General Social Survey, in which researchers have questioned thousands of Americans of all income levels going back to the 1970s — researchers even quantified how much happier the families were. The improvement was equal to the level of life satisfaction of someone whose annual income was $13,000 more a year, said Jens Ludwig, a professor of public policy at the University of Chicago and the lead author of the study.

This vast social experiment, involving 4,600 families in Los Angeles, New York, Baltimore, Chicago and Boston, tested a long-held theory that neighborhood is an important determinant of an individual’s success.

But there was little evidence that the new neighborhoods made much of a difference in either income or education, a disappointment for social scientists, who had hoped that the experiment would lead to new ways of combating poverty.

What researchers did find were substantial improvements in the physical and mental health of the people who moved. Researchers reported last year in The New England Journal of Medicine that the participants who moved to new neighborhoods had lower rates of obesity and diabetes than those not offered the chance to move. Beyond the increase in happiness, the new study found lower levels of depression among those who moved.

“Mental health and subjective well-being are very important,” said William Julius Wilson, a sociology professor at Harvard whose 1987 book “The Truly Disadvantaged” pioneered theory about concentrated poverty. “If you are not feeling well, it’s going to affect everything — your employment, relations with your family.”

The researchers measured quality of life using participants’ reports of their own well-being. Researchers asked: “Taken all together, how would you say things are these days? Would you say you are very happy, pretty happy or not too happy?”

A year after they entered the program, the families who had made the move were living in neighborhoods where about a third of the residents lived in poverty. In contrast, those who were not offered the chance to move lived in neighborhoods where half of the residents lived in poverty.

Professor Wilson said it was not surprising that education levels did not change significantly because many of the children who moved remained in the same school districts. And Lawrence Katz, an economics professor at Harvard and one of the study authors, said that the preference for educated workers was so strong that changing neighborhoods did not do much to improve job options for the participants, who were mostly African-American women without college educations.

Researchers said that though they did not know why people felt happier after moving, it probably had to do with feeling safer and less stressed. Nearly three-quarters of the families who signed up for the program said they had done so to get away from violence in dangerous neighborhoods.

Moving to a neighborhood that was less poor caused families that were making $20,000 a year to feel as happy as families making $33,000 a year, Professor Ludwig said.

Even more startling, researchers said, was the finding that families who moved into new neighborhoods that were just as racially segregated as the ones they came from, but were much less poor, reported much larger gains in feelings of well-being than those who moved to much more racially integrated neighborhoods that were nearly as impoverished.

That finding, Professor Katz said, is troubling for the future because economic segregation has grown steadily in the United States, since the 1970s, while racial segregation has been declining.

“The increased geographic isolation of the poor appears to have a pure adverse effect on health and well-being,” he said.

Improvements in health and well-being caused by moving to areas with less concentrated poverty “is not a magic bullet to eliminate poverty itself,” Professor Katz said. That would require major changes in the American economy. But he said it would improve lives for the families that experience it, and reduce the costs to taxpayers of medical care for them.