Per the Post:
Researchers from the University of Vermont mapped out the city’s happiest areas using a complex formula that can pinpoint tweet locations and rate their relative “happiness” and “sadness” based on certain key words.
Key words like "sun" and "yoga" (yay! happy!) and
sad words such as "hate" and "hell." (How about "another fucking rent hike"?)
(Also. Tricky: A word like "Woooooo!" could be seen as happy or sad, depending on who is on the receiving end of the Woooooo!, if researchers had actually measured Woooooo!)
The data found that the largest concentration of happy tweets came from the Times Square region. (Tourists: duh)
Elsewhere?
While most of Manhattan south of Central Park had people tweeting happily, there were pockets of unhappiness in the East Village, Chelsea and the area around City Hall. There were also a large number of sad tweets coming from the area around the United Nations.
No word if researchers measured emoticons.