The scientist Manuel Garcia-Herranz and his team at the Autonomous University of Madrid, Spain have elaborated an approach how to most effectively use the social media channel Twitter in disaster situations. Their technique involves small groups of "highly connected Twitter users as ‘sensors’ to detect the emergence of new ideas. They point out that this works because highly connected individuals are more likely to receive new ideas before ordinary users."
The team crunched six months of Twitter data dating from 2009. This involved 40 million users who together totted up 1.5 billion “follows” and sent nearly half a billion tweets, including 67 million containing hashtags. Garcia-Herranz and co looked, in particular, at 24 hashtags that were “born” shortly after the data set began. They concluded that these highly connected individuals detect "new hashtags about seven days earlier than the control group." That way, these Twitter "top users" could serve as an early warning system.
A second study by Aditi Gupta et al. backs this conclusion: "[T]he top users represent the topics and opinions of all the users in the community with 81% accuracy on an average. To understand a community, we need to monitor and analyze only these top users rather than all the users in a community."