Focus Paper: Characterizing Microblogs with Topic Models. Ramage, D. et al. 2010.
Related Paper: Beyond Microblogging: Conversation and Collaboration via Twitter. Honeycutt, C. and Herring, S. 2009
The paper that I read presents an analysis of dialog on Twitter, and specifically the use of the @ symbol. The authors analyze 37k tweets sampled from four 1-hour periods in order to answer four primary questions:
What is the language break-up of tweets over time, and do different languages use the @ symbol to different degree?
How do English tweets use the @ symbol?
What topics are present in tweets, and how does the presence of the @ symbol affect this distribution?
How does the @ symbol function with regards to interactive exchanges?
In answer to the first question, they found that the use of the @ symbol does not vary significantly over time or language. They categorized the use of '@' into a variety of categories: addresses, references, and several uses not related to the @username construction. Of the instances of '@' in a sample of 1500 tweets, 90% were addresses, 5% were references, and the last 5% was distributed among the remaining categories. The authors devised a semantic coding scheme for classifying tweets into one of twelve categories, and manually tagged around 200 tweets. Overall, they found that tweets with '@' in them tended to be more interactive; they were more likely to address others directly, make requests of others, or provide imformation.
To analyze dialog, the authors extracted all of the conversations that occurred in the sample of tweets, and found that the typical conversation was between two people, consisted of 3-5 tweets, and occurred over a period of 15-30 minutes. Further, they found that the use of the @ symbol was strongly tied to the presence of dialog.