Chetty stressed that the research didn't establish those factors cause greater mobility—only that they were common in those places where people had the best the odds of income gains. But, whatever the cause, the research demonstrates that factors influencing upward mobility happen early in life.
(Read more: World's richest have same wealth as 3.5 billion poorest)
"A lot of these differences (in mobility) we already see by the time kids are 18—in terms of teenage pregnancy rates or college attendance rates," he said. "What that said is we really need to find ways to intervene while kids are in school."
The importance of a quality primary and secondary education was underscored by the study. After controlling for income levels, upward mobility was higher in areas with higher test scores, lower dropout rates and smaller class sizes. Areas with greater local tax revenues, the main source of public school financing, also fostered more income gains.
The study also found that children born to the highest-income families in 1984 were 75 percentage points more likely to attend college than those from the lowest-income families, while the college gap for children born in 1993 shrank to 69 percentage points.
The researchers said that suggests that income mobility may have even increased slightly for college-aged Americans.