The reasoning is that wealthy states can provide infrastructure and so it's easier for residents to get their needs met. In addition, states with a greater proportion of artists and gays would also be places where residents can freely express themselves.
On average, well-being was highest in the Mountain states and West Coast states, followed by the Eastern Seaboard and then the Midwest and Southern states.
The researchers note that because a state scores high or low doesn't mean you could pluck out a resident and expect that person to be appropriately cheery or depressed. And not every state in the union sits exactly where you might expect on the list.
"We can only make generalizations about groups of people," said study researcher Jason Rentfrow of the University of Cambridge in England. "These results don't say wealthy people are happier than unwealthy people, [or that] people who live in areas where people are wealthy are happier."
Rentfrow and his colleagues came to their conclusions by analyzing data collected from more than 350,000 individuals who were interviewed between Jan. 2 and Dec. 30, 2008 as part of the Gallup Organization's Well-Being Index. The index includes six types of well-being: overall evaluation of their lives, emotional health, physical health, healthy behaviors (such as whether a person smokes or exercises), and job satisfaction.
Here are the top 10 states and their average well-being scores (out of a possible 100 points):
* Utah: 69.2
* Hawaii: 68.2
* Wyoming: 68
* Colorado: 67.3
* Minnesota: 67.3
* Maryland: 67.1
* Washington: 67.1
* Massachusetts: 67
* California: 67
* Arizona: 66.8
What makes us happy
To figure out why some states scored higher or lower than others, the researchers looked at the relationship between happiness levels and other variables, including economic indicators, education levels, personality factors and levels of inclusiveness.
They found that states with higher gross regional product (GRP) per capita (a state's level of productivity and standard of living), income levels and median housing value, were significantly happier than poorer areas. That's not too surprising, Rentfrow noted, as wealthier individuals tend to be healthier, because they are better educated and thus more knowledgeable about healthy behaviors, and they also likely have health insurance.
The happier states also tended to have a greater proportion of residents with advanced educations whose jobs were considered "super-creative," such as architecture, engineering, computer and math occupations, library positions, arts and design work, as well as entertainment, sports and media occupations.
The number of bohemians (such as artists), gays and foreign-born residents also boosted happiness scores. Take California, Minnesota and Massachusetts, which had higher inclusiveness scores and also made it to the top 10 list for well-being.
"We view that as suggesting that in these types of areas, there's more tolerance and with this increased tolerance people are freer to express themselves and to be who they are without feeling as though they have to censor themselves or conform a bit more to the status quo," Rentfrow told LiveScience.
Of the personality factors, neuroticism took a toll on a state's cheery count, suggesting people living in the happiest states are more relaxed than their gloomy counterparts. For instance, West Virginia, Mississippi and Kentucky were ranked as highly neurotic and showed lower well-being scores. Utah, on the other hand, had a significantly lower level of neuroticism than other states.
The new results, which are detailed in the December issue of the Journal of Research in Personality, do have their limitations.
For one, the differences in well-being are small, a range of about 10 points on a 100-point scale. "When we compare nations, there are much larger differences, say, between a poor African nation and Denmark," said Ed Diener, a psychologist at the University of Illinois at Urbana-Champaign who studies well-being. Diener wasn't involved in the current research.
For instance, while Utah is about 12 percent happier than Kentucky, Diener said that Denmark has scored about double that of Togo, Africa, regarding well-being. Even so, Diener noted, "given the strong pattern of explainable findings found by the authors, I would say they are definitely onto something interesting and important."
In addition, not all states fit into the researcher's overall model of what makes for a happy area. For instance, the top three states, Utah, Hawaii and Wyoming are outliers, as they aren't considered the wealthiest of the pack.
Diener points out that Utah is conservative, and research has suggested such right-leaning individuals are a bit happier than others. Hawaii's ranking could be due to a relaxed culture, he said, adding that the three states may just have strong families and social relationships.
Most research on who's happiest has focused on differences between countries rather than differences within say the United States. And those studies with a state focus have not included factors to explain the reasons well-being was higher in one region compared with another, as the new study did.
"The fact that there are differences in well-being between states isn't of much use unless we know that the differences are related to something," Rentfrow said. "If there are differences in well-being, but those differences are not related to anything, then it's not clear that the differences are really important."
As a result, the new results have practical implications.
"If I were a state government person, I could use the information, if my state scored high, to attract new talent," Diener said. "After all, people will want to go to happy places and be around happy people."
And for low-scoring states Diener suggests figuring out changes that should be made to boost such scores. "Our research shows that happy individuals are on average healthier and live longer, have higher incomes, better social relationships and are better citizens," Diener said. "Therefore, aiming to increase the happiness in one state is a valid goal."