More evidence that economists in general and dismal scientists at the Federal Reserve in particular are hopelessly and dangerously detached from reality (i.e., guided by the mistaken belief that, if something doesn’t exist in their models, neither does it exist in the real world) comes via this Associated Press story about a new study by the central bank detailing how wild speculation drove the late, great U.S. housing bubble.

A new federal report shows that speculative real estate investors played a larger role than originally thought in driving the housing bubble that led to record foreclosures and sent economies plummeting in Nevada, California, Arizona, Florida and other states.

Researchers with the Federal Reserve Bank of New York found that investors who used low-down-payment, subprime credit to purchase multiple residential properties helped inflate home prices and are largely to blame for the recession. The researchers said their findings focused on an “undocumented” dimension of the housing market crisis that had been previously overlooked as officials focused on how to contain the financial crisis, not what caused it.

More than a third of all U.S. home mortgages granted in 2006 went to people who already owned at least one house, according to the report. In Arizona, California, Florida and Nevada, where average home prices more than doubled, investors made up nearly half of all mortgage-backed purchases during the housing bubble. Buyers owning three or more properties represented the fastest-growing segment of homeowners during that time.

“This may have allowed the bubble to inflate further, which caused millions of owner-occupants to pay more if they wanted to buy a home for their family,” the researchers noted.

I saw this last week when it was originally published and should have mentioned it at the time (the report from the New York Fed can be found here), but, now that it’s getting lots of attention in the mainstream media it’s a case of better late than never.