<http://schema.org/articleBody>
"A recent study of Twitter use reveals that the general public appears to be less happy than previously. University of Vermont researchers surveyed more than 4.5 billion tweets and discovered which words were used the most and how they characterize our day-to-day mood.\n\u201CAfter a gradual upward trend that ran from January to April 2009, the overall time series has shown a gradual downward trend, accelerating somewhat over the first half of 2011,\u201D the researchers wrote in a recent issue of the journal PLoS ONE.\nCheck out the video above to learn more.\n"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2011/12/20/happiness-twitter/>