Krueger, former chairman of the White House Council of Economic Advisors, plotted economic inequality in 10 developed nations against the ability of the children in each country to climb the income ladder. Where wealth was concentrated in the hands of a few, daughters and sons of the less fortunate were less likely to advance, the Gatsby Curve showed.

In a June speech, Krueger projected the U.S. will have the highest levels of inequality and immobility of those developed nations.

Income inequality in the U.S. has been rising since the 1980s, suggesting that the fortunes of today’s youth may be more heavily dependent on their parents. Between 1979 and 2007, $1.1 trillion in annual income shifted to the top 1 percent of households, said Krueger. Not since Gatsby’s Roaring Twenties has so much income been collected by so few, the Princeton University economics professor said.

“The rise in inequality has gotten to the point where we have to worry about it being unhealthy,” Krueger said in an interview. “It’s bad for growth.”

Some say the portrayals of inequality and mobility aren’t so clear cut. Heritage Foundation’s Donald Schneider notes that the size and homogeneity of countries skews the results.

Comparing the U.S., the third-most populous country in the world at about 317 million, with Denmark and its population of 5.6 million as Krueger does with his Gatsby Curve “may generate results that are not as useful in drawing conclusions about the mobility conditions in each country,” Schneider wrote in a July paper.

“Dealing with the data itself is difficult, but there’s entirely different reasons across countries that make it hard to give you an apples-to-apples comparison,” Schneider said in an interview. “When you get into international comparisons, not only do you have those local economic factors but also things you wouldn’t really consider, like demographic heterogeneity.”

Federal Reserve

Within the U.S., elements of economic mobility are more obvious to some. In its attempt to rescue the economy from the worst recession since World War II, the Federal Reserve may have exacerbated income disparity, said Joseph LaVorgna, chief U.S. economist at Deutsche Bank Securities Inc. in New York.

Unprecedented monetary stimulus has led to rising home and stock prices, sources of wealth that are out of reach for some Americans, he said.

The record bond buying, known as quantitative easing, has caused the Fed balance sheet to balloon to $3.75 trillion in total assets from $877 billion in August 2007.