—"EU versus USA," Fredrik Bergström and Robert Gidehag, Timbro
Monogamy is the key to a thriving sex life, according to a National Bureau of Economic Research study aimed at quantifying the links among income, sex, and general happiness. Married people have considerably more sex than swinging singles and gay divorcees, and the "happiness-maximizing" number of sexual partners in a given year is almost exactly one. Rising wealth has no positive effect on the frequency of sex, and increased education actually has a slightly negative effect, particularly among men. (This is unfortunate news for the well-educated, since they are the group for whom sexual activity has the highest impact on happiness.) Strikingly, men consistently report more sexual activity than women do. Unless a disproportionate number of men in the sample population are gay or visit prostitutes, it "is not easy to see how this gender difference can be genuine," the authors write; they gently suggest that this discrepancy may be attributable to "exaggerated memories" among the male population.
—"Money, Sex, and Happiness: An Empirical Study," David G. Blanchflower and Andrew J. Oswald, NBER
Over the first two thirds of the twentieth century black Americans abandoned the South in droves, producing a "great migration" northward in search of manufacturing jobs and more social equality. Now a Brookings Institution analysis suggests that a reverse "great migration" seems to be picking up speed, driven by an improved economic and racial climate in the South and the strong cultural and familial connections that many blacks still feel with the region. According to Brookings, migration accounted for a net gain of more than 600,000 black residents in the South from 1975 to 2000, while the rest of the country lost black residents. College-educated blacks are leading the way southward, and the biggest beneficiaries of the shifting migration patterns and attendant "brain gain" are booming "New South" cities such as Atlanta, Charlotte, and Memphis. But the trend extends across all the southern states except Arkansas, Louisiana, and Mississippi—and even in those states the outflow of blacks has slowed dramatically over the past decade. Meanwhile, cities in the Rust Belt and the Northeast, in particular, have been losing black residents for some time, and California's long reign as a "black migrant magnet" seems to have ended. From 1965 to 1970 and again from 1975 to 1980 California's net gain of black residents was greater than any other state's; in the last five years of the 1990s, however, its net loss of black residents was larger than that of any other state except New York.
—"The New Great Migration: Black Americans' Return to the South, 1965—2000," William H. Frey, Brookings Institution
Forget McDonald's—it's the leafy avenues and spreading parking lots of suburbia that are to blame for America's obesity epidemic. According to an exhaustive new study examining the link between population density and health in 448 American counties, the residents of the country's more sprawling counties tend to be heavier and have more weight-related chronic illnesses—particularly high blood pressure—than the residents of more densely populated counties. The study relied on a U.S Census—based "Sprawl Index" that assigned the lowest numerical scores to the most sprawling counties (352 points for crowded New York County; 63 points for suburban Geauga County, outside Cleveland), and found that for every fifty-point increase in the degree of sprawl, the odds of a county resident's being obese rose by 10 percent. Cities encourage walking and physical fitness, the authors argue, whereas suburban homes are so far from friends, stores, and workplaces that even the most health-conscious residents are forced off the sidewalk and behind the wheel.
—"Measuring the Health Effects of Sprawl," Barbara A. McCann, Reid Ewing, Smart Growth America