Increasing the Reach of Government Social Media: A Case Study in Modeling Government–Citizen Interaction on Facebook Jorge Goncalves, Yong Liu, Bin Xiao, Saad Chaudhry, Simo Hosio, and Vassilis Kostakos Facebook posts compete for human attention in a zero-sum game; this makes it a challenge for government organizations to engage with their citizens through this medium. In a large-scale longitudinal study we investigate what makes Facebook posts popular (seen by many) and effective (commented, liked, or shared by many) in a nonprofit context: the official Facebook page of a mid- sized city (Oulu, Finland). We model the competition dynamics that shape the fate of Facebook posts using Structural Equation Modeling. Our analysis reveals that audience demographics, the timing of posts, and the media type of post are significant factors in post reach and effectiveness, and argue that our method can be applied to other contexts to determine which factors can lead to improved government–citizen communication and engagement. Finally, we argue for more actionable research to be conducted on the use of social media by government. KEY WORDS: e-Government, social media, Facebook, communication, public engagement Introduction There is substantial evidence to suggest a gradual rise in the prevalence of social media among citizens of all walks of life (cf. Chui, Manyika, Bughin, & Dobbs, 2012). Today, one in five hours spent online is on social networks (Chui et al., 2012), and Facebook, with over one billion monthly active members (The Wall Street Journal, 2012), is currently the second most visited website on the Internet, besides Google (Alexa, 2013). The use of social media has become such a landmark cultural, social, and economic phenomenon (Chui et al., 2012) that various commercial and noncommercial organizations have invested considerable resources in the use of social media for a diversity of purposes, including marketing, loyalty enhancement, and customer feedback. Albeit with a certain delay, government organizations are now increasingly experimenting with social technology to communicate with their constituents. Social technologies have been seen as a powerful set of tools to reinvent government–citizen relationships (Picazo-Vela, Gutie ´rrez-Martı ´nez, & Luna-Reyes, Policy & Internet, Vol. 7, No. 1, 2015 80 1944-2866 # 2015 Policy Studies Organization Published by Wiley Periodicals, Inc., 350 Main Street, Malden, MA 02148, USA, and 9600 Garsington Road, Oxford, OX42 DQ.