The happiest states:
8. South Carolina
Their results come from a comparison of two data sets of happiness levels in each state, one that relied on participants' self-reported well-being and the other an objective measure that took into account a state's weather, home prices and other factors that are known reasons to frown (or smile).
The self-reported information came from 1.3 million U.S. citizens who took part in a survey between 2005 and 2008.
"We wanted to study whether people's feelings of satisfaction with their own lives are reliable, that is, whether they match up to reality - of sunshine hours, congestion, air quality, etc - in their own state," Oswald said.
The results showed the two measures matched up. "We were stunned when it first came upon our screens because no one has ever managed to produce a clear validation before of subjective well-being, or happiness, data," Oswald said.
They were also surprised at the least happy states, such as and , which landed at the bottom two spots on the list.
"We were struck by the states that come at the bottom, because a lot of them are on the East Coast, highly prosperous and industrialized," Oswald said. "That's another way of saying they have a lot of congestion, high house prices, bad air quality."
He added, "Many people think these states would be marvelous places to live in. The problem is that if too many individuals think that way, they move into those states, and the resulting congestion and house prices make it a non-fulfilling prophecy."
Would you be happier in another state?