The World Happiness Index is a social experiment that aims to numerically gauge the global emotional state of humanity through the use of social networking information syndicated by Twitter. Since late 2008, the World Happiness Index has interpreted moods from over 27 million tweets from internet users around the globe.
The Index is calculated by parsing real-time twitter status updates syndicated by the Twitter's Spritzer Stream, while attempting to interpret a mood from each status update we see. We then build a daily average using all the data we collect for the day. The higher that number is, the happier the world we perceive through this data seems to be.
This really started as a fun experiment to use the Twitter API. It has now evolved into something that I personally find quite interesting. Is it useful for anything more than being interesting? I'm not sure. If you would like to try doing something with the data, I have made it available by API, and a simple download link on our Statistics page.