Public Protests and Policy Making*
研究了请愿和公众抗议作为信息聚合机制的局限性，发现当公民个人信号不够精确时，即使人数再多也无法有效聚合信息，但社交媒体可能改善这一情况。
Abstract Technological advances and the development of social media have made petitions, public protests, and other form of spontaneous activism increasingly common tools for individuals to influence decision makers. To study these phenomena, in this article I present a theory of petitions and public protests that explores their limits as mechanisms to aggregate information. The key assumption is that valuable information is dispersed among citizens. Through petitions and protests, citizens can signal their private information to the policy maker, who can then choose to use it or not. I first show that if citizens’ individual signals are not sufficiently precise, information aggregation is impossible, no matter how large is the population of informed citizens, even if the conflict with the policy maker is small. I then characterize the conditions on conflict and the signal structure that guarantee information aggregation. When these conditions are satisfied, I show that full information aggregation is possible as the population grows to infinity. When they are not satisfied, I show that information aggregation may still be possible if social media are available.