The Role of Protest Experience and Social Networks in Protest Movements in Hong Kong

Researchers:
Davide Cantoni
David Y. Yang
Noam Yuchtman
Y. Jane Zhang
Fieldwork by:
Location:
Hong Kong
Sample:
849 university students
Timeline:
2017 - 2018
Target group:
  • Higher education and universities
  • Students
  • Adults
Outcome of interest:
  • Voter behavior
AEA RCT registration number:
AEARCTR-0002301
Data:
OpenICPSR
Partners:

Political movements and related protests have been important drivers for economic, social, and political change, but there is limited evidence on the causes of individuals’ sustained participation in such movements. In Hong Kong, researchers conducted a randomized evaluation to test the impact of indirectly incentivizing protest participation on sustained participation in a political movement and to identify the role social networks play in protest turnout. Indirectly incentivizing participants to attend a political protest increased their participation regardless of how many of their peers received the same incentive. Participants’ subsequent protest participation remained persistently higher a year later, but only when at least half of their social network was also incentivized to attend the initial protest. 

Policy issue

Political movements and related protests have been important drivers for economic, social, and political change. Historically, political rights have often arisen from long-running movements requiring sustained political engagement from citizens, such as the women’s suffrage movements or the anti-apartheid movement in South Africa. However, there is limited evidence on the causes of individuals’ sustained participation in political movements. Does attending a protest impact individuals’ subsequent participation in a given political movement? Are individuals influenced by the political participation of others in their social networks when deciding to protest?

Context of the evaluation

At the time of the evaluation in 2017 and in the two decades prior, Hong Kong was experiencing a democratic movement to demand political rights from the Chinese Communist Party. Each year, people gathered for peaceful marches in protest of the Chinese government on July 1, the anniversary of Hong Kong becoming a special administrative region within the People’s Republic of China in 1997. The protests aimed to achieve policy concessions and represented an important component of the broader movement. Protest turnout varied from under 20,000 to over 500,000 participants across the years. The study took place during the 2017 and 2018 July 1 marches, when about 50,000 people participated each year. 

Details of the intervention

Researchers conducted a randomized evaluation to test the impact of indirectly incentivizing protest participation on subsequent participation in a political movement and to identify the role social networks play in protest turnout. Researchers randomly assigned a subset of Hong Kong University of Science and Technology students taking an online survey to receive a prompt indirectly encouraging them to attend the July 1, 2017 march. The prompt indirectly encouraged participation by offering students a reward equivalent to US$45 if they reported an estimate for how many people attended the march, and uploaded photos to support their estimated crowd size.1 The prompt inviting them to participate read:

  • “Because many students attend the events of July 1, we are asking a subset of survey participants to help us get a better estimate of the July 1 March attendance.… We would like to ask you to participate in this scientific endeavor. This should take only 5 minutes of your time while you are at the March.… Once you have uploaded all the information, we will pay you additional HK$350 [US$45  ] for your time and effort.”

Students randomly assigned to receive this prompt also received an email the day before the march with instructions on how to estimate march attendance, submit information and photos for the task online, and receive their reward. Students assigned to the comparison group did not receive the prompt or email, but like all participants, answered questions about their and their peers’ political preferences, beliefs, and behaviors, including protest attendance, during the online survey.   

To identify the role of social networks on protest participation, researchers also randomly varied the proportion of students receiving the protest incentive across 98 major-cohort groups, a relevant social group based on students’ degree focus, graduating year, and shared course work. This meant groups would have either 0 percent, 1 percent, 50 percent, or 75 percent of students being indirectly incentivized to participate in the march .Overall, approximately 45 percent of students received the prompt about the July 1 march, while the remaining students did not.   

Researchers resurveyed participants immediately after the July 1, 2017 march to measure the short-run impacts on protest participation, political beliefs, and preferences, and again immediately before and after the July 1, 2018 march to measure long-run impacts. In total, 849 students completed all survey rounds and are the focus of the study.  

The paper includes a dedicated appendix section (Appendix B) discussing ethical considerations.

In addition to receiving ethical review and approvals from institutional review boards, researchers made efforts to address potential ethical concerns and ensured minimal risks to participants before the evaluation began. First, the reward of HK$350 (US$45) for reporting on the protest crowd size was designed to be comparable to prevailing local wages given the number of hours expected to complete the task, limiting the risk of coercing participation. Further, when researchers offered other participants the same monetary incentive to count the crowd size at a subway station a week later (instead of at a protest), the share of students who took up the offer and completed the task was very similar, suggesting participants perceived the two tasks as having a similar degree of risk.  

The researchers and ethics review boards also assessed a minimal ex ante risk level no larger than the risks the general population encounters in daily life. Participation in the annual July 1 marches was unambiguously legal at the time, with broad participation across social groups and regular statements from the government affirming citizens’ right to protest following prior marches. All marches had been peaceful in the years prior to the study, with police only arresting nineteen and charging five people out of the 1.35 million participants from 2003-2018.2 Moreover, during ten of the fifteen marches from 2003-2018, police made no arrests at all. After the 2017 and 2018 protests, researchers also assessed the risk level to be minimal, as the marches remained peaceful and no protesters received charges for any offenses.   

The researchers also took steps to protect and de-identify data from the study. Identifiable information on participants was only collected and used to contact participants and process study payments. The researchers de-linked identifiable information from the remaining data and stored it separately in an encrypted format. They did not share any data with government bodies, organizations, or the school administration.  

The number of individuals participating in this evaluation was also small relative to the size of the marches, with the program only affecting total turnout by about 0.1 percent. Lastly, researchers did not allow minors to participate in the study. For more on the researchers’ discussion of ethical considerations, see Appendix B.

Results and policy lessons

Researchers found that indirectly incentivizing students to attend a political protest made them more likely to attend, regardless of how many of their peers received the same incentive. Students’ subsequent protest participation remained persistently higher a year later, but only when a sufficient fraction of their social network was also incentivized to attend the initial protest.   

Initial protest participation: The prompt indirectly incentivizing protest participation increased turnout to the July 1, 2017 protest by 11 percentage points  among students receiving the message, relative to a turnout rate of 1.2 percent among students receiving no prompt.

Subsequent protest participation: On average, students prompted to attend the 2017 protest were 5 percentage points more likely to attend the July 1, 2018 protest, relative to a turnout rate of 2.5 percent   among students in the comparison group.

Role of social networks: In 2017, protest participation increased equally among students receiving the incentive to attend the July protest, regardless of what proportion of their major-cohort group received the same prompt. This suggests that social networks did not influence students’ decision to attend the 2017 protest, but rather students made their decisions individually.   

In contrast, social networks did influence students’ decisions to attend the 2018 protest. Students who had a larger proportion of their major-cohort group receive the protest incentive in 2017 attended the 2018 protest at a higher rate than those from less incentivized groups.  Incentivized students in major-cohorts where 50 percent or 75 percent of the group received the protest incentive in 2017 were 2.9 and 8.4 percentage points more likely to attend the 2018 protest, respectively, relative to students who did not receive the incentive in the same groups. Incentivized students from major-cohorts where only 1 percent of the group received the incentive were slightly less likely to attend the 2018 protest than students who did not receive the incentive in the same groups.  

Researchers found evidence suggesting that new or stronger friendships formed through the 2017 protest contributed to later protest participation by making it easier for students to coordinate amongst themselves. Incentivized students in groups with a high proportion of incentivized peers reported new political friendships more often. Further, researchers found that coordination costs among these students lowered. That is, they were more likely to turn initial plans to attend a protest into actual protest attendance in 2018, potentially due to gaining information on logistics like transportation from their changing social networks.   

Together, these results have important implications for the evolution of political movements: a one-time mobilization towards protest participation can have long-term impacts, with social networks influencing whether political engagement is sustained over time.  

Bursztyn, Leonardo, Davide Cantoni, David Y. Yang, Noam Yuchtman, and Y. Jane Zhang. 2021. "Persistent Political Engagement: Social Interactions and the Dynamics of Protest Movements." American Economic Review: Insights, 3 (2): 233-50.

1.

The reward of HK$350 (US$45) was in line with local prevailing wages and the time commitment expected for completing the task.

2.
Of the nineteen arrests came only five charges and five convictions as of 2019, with most sentenced to eighty hours of community service. The most severe sentence was six weeks imprisonment for assaulting a police officer.