Information Cascades & Crisis Responses
A critical moment in which information cascades apply is both during and after a crisis – whether that be a natural disaster or some other type of emergency. In these moments, the sharing of information is vital and is closely tied with social media, one of the main ways of information sharing in the modern world.
In an information cascade in a social system, an individual has the decision whether to adopt a certain behavior or not. These decisions are made sequentially after other people, where the individual can observe the actions others around them are doing and thus may have their own decision be influenced by the decisions they observe the people around them take. In the context of an emergency, individuals can see information on the crisis and choose whether or not to share it, or choose what information is most important to share to their own followers on social media. These decisions are largely impacted by the decisions of others on social media that they observe, and are important to look into as having public awareness on emergencies is crucial.
One such research article conducted by Hui et al. investigates into this topic, and forms a preliminary model of how such information cascades on social media work when responding to a crisis.
It looks at information cascades on Twitter that respond to a crisis event, alongside alert messages from emergency managers. Twitter was the chosen social media website due to its 140 character limit producing concise messages that are easy to track as well as its retweeting feature acting as an efficient way to measure the propagation in an information cascade. Past research also showed that more user interactions done on Twitter are on sharing information one-way rather than reciprocal interactions between users and followers, further allowing information cascades to be tracked.
This research article found that during an emergency, users on Twitter gather and share critical emergency information posted by public officials and news outlets to their own network of followers. This was demonstrated during events such as the 2007 southern California fires and 2009 Oklahoma Grassfires. This was seen numerically as well, as activity on Twitter during an emergency is focused more on information sharing through retweets and has a lower percentage of reply tweets than when compared to general Twitter usage.
The information cascade in these emergencies occurs when users on Twitter see information on the emergency at the right time where it is relevant and then decide to pass the information onward. In addition, by observing the actions of others, such as tweets being posted or retweeted by others, information cascades are also formed. Users make these decisions on what to retweet, on one part, based on their geographical proximity to the event. For instance, people who are closer in proximity to the event may post more local specific news and announcements while others who are more distant may post more general news articles. The general rule of the information cascade is that users retweet messages that they find are important to share and pass on to others they know.
The general preliminary model of how this cascade works starts with a user being susceptible to new information that they may become exposed to when browsing Twitter. This is called an uninformed state. This user may then either see a tweet and not find it relevant, with this state being called uninformed. On the flip side, the user may see a tweet and find it relevant and thus be influenced by it (a state called undecided/believed). When users are influenced by a tweet, they may retweet it to all of their follows or direct message it to select users as a way of sharing information, or even make a new tweet related to the general topic of the information. The information cascade then originates from the information sources on the crisis and propagates through the users that follow this information source and who make decisions on whether or not to retweet it and share it to their own set of followers.
These insights on information cascades in response to emergencies, and further understanding of this topic, can allow emergency managers that must provide this vital information in times of crises better understand how their information will be diffused and thus how to more effectively spread information to those who need it most using social media.
Source:
https://dl.acm.org/doi/10.1145/2187980.2188173