claims that regular religious participation leads to better education, higher income and a lower chance of divorce. His results (based on data covering non-Hispanic white Americans of several Christian denominations, other faiths and none) imply that doubling church attendance raises someone's income by almost 10%.The summary points out that ethnic density can make a group worse off ("ghettoization"), which Gruber controls for by looking at "the density of 'co-religionists'" not of the same race. He says that "a 10% increase in the density of co-religionists leads to an 8.5% rise in churchgoing" and that
a 10% increase in the density of co-religionists leads to a 0.9% rise in income. In other words, because there are lots of non-Polish Catholics in Boston and a few in Minnesota, Poles in Boston both go to church more often and are materially better off relative to, say, Swedes in Boston than Poles in Minnesota relative to Swedes in Minnesota.If this is accurate, what's actually going on here? Suggestions offered in the Economist summary: Churchgoing increases one's network of connections, making business dealings smoother; churchgoing provides a form of insurance against social or economic setbacks; churchgoing promotes an increase in education; churchgoing reduces the stress of life. The first two of these, and perhaps the last, strike me as plausible; whether or not churchgoing promotes education likely depends a great deal on the particular sect or denomination.