Examining the roles of social media and alternative media in social movement participation: A study of Hong Kong's Umbrella Movement.

• This study examines the effects of two digital media use over protest participation. • The indirect effects through two socio-psychological variables were tested. • This study was contextualized in the Umbrella Movement in Hong Kong in 2014. During the recent wave of pro-democracy movement across the world, new media technologies play a vital role in mobilizing participants. Much scholarly attention has been paid to the role of social media in empowering grassroots movements, but the rise of alternative media was somehow ignored. This study examines the impacts of social media and alternative media on social movement participation. The data came from a survey of 769 students from eight public universities in Hong Kong at the height of the Umbrella Movement. The findings revealed that acquisition of political information from social media and alternative media is associated with social movement participation through different mechanisms. Specifically, social media serve as an echo chamber where people are motivated to participate by perceiving a homogeneous opinion climate and forming a pro-protest attitude. In contrast, alternative media serve as an attitude intensifier to facilitate social movement participation. [ABSTRACT FROM AUTHOR]