Summary by Patrick Skevik What is Twitter, a Social Network or News Media? ------------------------------------------------ This paper studies the content of Twitter in an attempt to determine whether Twitter is a social network or a news media. They crawled twitter for a few weeks in order to gather data they can analyse. This includes user profiles, trending topics and twitter messages (tweets). They compare several methods of ranking in order to find the most influential people and compare each method against each other to meassure the ranking system against each other. This is based on the number of followers, PageRank algorithm and the number of retweets. Their analysis show that news is ranked high when it comes to retweets compared to number of followers and PageRank. They then attempt to classify trending topics which seems to show that news is indeed a big part of the trending topics. Although this was done during the Iranian election which might have caused some minor bias towards the news. What is Twitter, a social network or a news media? --- Summary by Ying Li This study aims at identifying the characteristics of Twitter as a social network and its function in terms of spreading and sharing information among users. In order to do that, authors crawled the entire Twittersphere and obtained 41.7 million user profiles. The pattern that is discovered in the data analysis shows Twitter as an online social network, has very different characteristics compare to human social networks, in the sense that Twitter has non-power-law follower distribution, a short effective diameter, and low reciprocity. The study applies different methods such as PageRank algorithm, Retweets and number of followers to rank the users of Twitter, in order to identify the influential elements in Twitter. The result reveals a gap between the number of followers and the popularity of one¡ã?s tweets. The study also analyzes the spreading pattern of trending topics and the pattern of retweeting. Suggested questions: What¡ã?s the implications of the research result to future research or developer¡ã?s work? ----- BEGIN SUMMARY ------ What is Twitter, a Social Network or a News Media? summary by guangyu ------------------------------------------------------------------------------ The paper introduce the way Twitter works. Analysising the varies Data crawled from all user of the Twitter with large scale . IT presents the new methods of distribution compared with other social network. The function of Retweet plays an important role which leading twitter not only become a popular way of social network but also a effective media . The differences and advatages compared to the other traditional social network and mediea: lower rate of Reciprocity shorter path length longer time exist higher efficiency Some of the properties evaluated in these networks were: Comparison among Rankings four modles to classified popularity patterns The modle of Retweet trees is interesting At the ends, it introduce the related subjetcs including sociology, marketing,epidemiology ,large-scale information diffusion. questions The methods of ananlysis geographic location according to the time zone is not precise metrics. ---------END SUMMARY------------