The old frontier was improving the way the federal poverty line is calculated—a challenge Smeeding remembers explaining to National Journal decades ago. The Census Bureau has calculated the poverty rate pretty much the same way since the early 1960s: Take the cost of a minimal diet, multiply it by three, and adjust for family size, composition, and age. The formula takes into account only government benefits issued in cash—leaving out benefits such as food stamps—and poverty thresholds don't adjust to reflect the local cost of living.
A few years ago, the Census Bureau started to issue an experimental poverty measure based on the recommendations of the National Academy of Sciences. It's called the Supplemental Poverty Measure, and it takes into account both cash and noncash benefits; defines minimal household expenditures as a function of food, clothing, shelter, and utilities; and factors in other required expenses, such as child support payments.
The SPM's estimate for the national poverty rate and the official rate aren't that different. But the SPM tells us much more about how government programs work. Without food stamps, for example, the poverty rate for children would have been 3 percentage points higher in 2012. Without Social Security, the poverty rate for the elderly would have been almost 40 percentage points higher.
At the state and local level, policymakers are developing SPM-like measures and using them to shape antipoverty policy. New York City started estimating such a measure in 2008, and the data have informed Mayor Bill de Blasio's antipoverty agenda. The most recent city report found that almost half of New Yorkers were living in poverty, or close to it.
The Columbia study tries to go even further than the city's measure—which relies on census survey data—by following the same people over a two-year period. Funded by the New York City-based Robin Hood Foundation, the project is called the Robin Hood Poverty Tracker.
"We know that falling one dollar above or below any given poverty line may not capture the full dimensions of disadvantage," says Wimer, codirector of the Center on Poverty and Social Poverty at Columbia University. "So we spend a lot of time asking about what we call material hardships."
The study began with a baseline phone survey that asked people in-depth questions about their personal finances, and mental and physical health. Questions such as: Over the past year, were you forced for financial reasons to stay in a shelter? Do you have any health problems that prevent you from working?
The researchers visited social-service agencies to recruit participants who don't have phones or home addresses, and who don't usually get counted. Every three months, they've followed up with additional questions. Survey findings are statistically adjusted to represent the city as a whole.