Some experts say that's a dangerous path that could allow governments to use positive public perceptions as an excuse to ignore problems.
As an example of the risks, some said, the Gallup poll may have been skewed by a Latin American cultural proclivity to avoid negative statements regardless of how one actually feels.
"My immediate reaction is that this influenced by cultural biases," said Eduardo Lora, who studied the statistical measurement of happiness as the former chief economist of the Inter-American Development Bank.
"What the empirical literature says is that some cultures tend to respond to any type of question in a more positive way," said Lora, a native of Colombia, the 11th most-positive country.
For the nine least positive countries, some were not surprising, like Iraq, Yemen, Afghanistan and Haiti. For others at the bottom, Armenia at the second lowest spot, Georgia and Lithuania, misery is something a little more ephemeral.
"Feeling unhappy is part of the national mentality here," said Agaron Adibekian, a sociologist in the Armenian capital, Yerevan.
"Armenians like being mournful; there have been so many upheavals in the nation's history. The Americans keep their smiles on and avoid sharing their problems with others. And the Armenians feel ashamed about being successful."
