45. Enkele wetenschappelijke onderzoeken… Kwak et al. (2010): compared three different measures of influence: the number of followers, Page-Rank and number of retweets. Cha et al. (2010) also compared three different measures of influence: the number of followers, the number of retweets and the number of mentions. Finally, Weng et al. (2010) compared the number of followers with a modified Page Rank measure that accounts for the topic.