Ever wonder exactly what kind of emotion people mean to express with some of the more obscure emoticons, like :/, <3, or ^_^?  Alex Davies, a Gates scholar at the University of Cambridge, has too, so he created a Twitter sentiment analysis list of ~5000 common words used on Twitter, each with their associated joint log probability for appearing in a happy tweet or sad tweet.

He also created visual Wordle clouds from the words associated with Twitter emoticons.

“Twitter contains a wealth of sentiment information which researchers and businesses are very interested to explore so they can assess the changing global mood on different issues in real time and make predictions based on this,” he said.

Examples of unusual emoticons:

^_^	Associated with more immediate pleasures such as food and holidays and words like shopping, lunch, dinner and chocolate (East Asian style)
-_-	Indicative of frustration and is associated with words such as dumb, lame, dick and bitch (East Asian style)
<3	Associated with words such as love, music, amazing, proud, beautiful, thankful, Jesus and Justin {looks like a heart on its side)
:/	Indicative of a half-awake, slightly annoyed state, associated with words such as shift, sleeping, busy, class and Monday

“What is interesting is that two emoticons that essentially represent the same sentiment, such as and ^_^, actually differ substantially in how they are used, and we can see this in the images of the words,” he said.

“The creation of new emoticons has essentially stopped, but the context and usage of existing ones is constantly evolving. Take for example Asian style emoticons, such as ^_^ (happy) and -_- (sad). Initially these were used almost exclusively by Asian online communities, but have slowly been adopted by different Western sub-cultures and have taken on subtly different meanings.