“…Because Twitter feeds can contain a massive amount of information and text, it is important to be able to limit the amount of data when using Twitter as a source of research material (Elson et al, 2012). The strategy to base the sample on the use of specific hashtags has been proposed in previous studies (see, for example, Bruns and Burgess, 2011;Bruns and Stieglitz, 2013;Elson et al, 2012;Heverin and Zach, 2012;Larsson and Moe, 2013). In this study, consideration has been made for both the subject of the tweets as well as to the time dimension, and only tweets from the day of the attacks up until 2 weeks after (a time frame used previously in, for example, Stone and Pennebaker, 2002), and only those containing the hashtags #oslo, #oslexpl, #osloexplosion, #explosion, #osloblast, #utøya, #utoya, #utöya, #utoeya, #breivik, #prayfornorway and/or #terrorist, were included in the sample.…”