Chen, Simin Michelle2019-05-132019-05-132019-03https://hdl.handle.net/11299/202913University of Minnesota Ph.D. dissertation. March 2019. Major: Mass Communication. Advisors: Joanne Miller, Sid Bedingfield. 1 computer file (PDF); vi, 256 pages.Since the Arab Spring of 2011, scholars have debated the efficacy of social media in facilitating offline collective action. This dissertation seeks to fill a gap in that literature by examining the role of social ties in determining intention to participate in collective action. Using a mixed methods approach involving statistical analysis of survey results and in-depth interviews, this study examines how the Minnesota chapter of the Women’s March in opposition to President Donald Trump used Facebook to engage and mobilize supporters. Findings show that aspects of tie strength such as reciprocity, duration, affect have different impact on intention to participate in high- and low-cost political actions. Similarly, the publicness of supporters’ political action on Facebook has differing effects on intention to participate in collective action depending on supporters’ tie strength with the chapter. Findings from this study have practical implication for social movement organizers seeking to energize, grow, and mobilize supporters using social media.encollective actiongrassroots organizingpolitical participationsocial mediasocial movementsThesis or Dissertation