Wang Peng, Li Jinyi, Ma Yinjie, Jiang Zhiqiang
School of Business, East China University of Science and Technology, Shanghai 200237, China.
Research Center for Econophysics, East China University of Science and Technology, Shanghai 200237, China.
Entropy (Basel). 2021 Dec 11;23(12):1667. doi: 10.3390/e23121667.
Charitable crowdfunding provides a new channel for people and families suffering from unforeseen events, such as accidents, severe illness, and so on, to seek help from the public. Thus, finding the key determinants which drive the fundraising process of crowdfunding campaigns is of great importance, especially for those suffering. With a unique data set containing 210,907 crowdfunding projects covering a period from October 2015 to June 2020, from a famous charitable crowdfunding platform, specifically Qingsong Chou, we will reveal how many online donations are due to endogeneity, referring to the positive feedback process of attracting more people to donate through broadcasting campaigns in social networks by donors. For this aim, we calibrate three different Hawkes processes to the event data of online donations for each crowdfunding campaign on each day, which allows us to estimate the branching ratio, a measure of endogeneity. It is found that the online fundraising process works in a sub-critical state and nearly 70-90% of the online donations are endogenous. Furthermore, even though the fundraising amount, number of donations, and number of donors decrease rapidly after the crowdfunding project is created, the measure of endogeneity remains stable during the entire lifetime of crowdfunding projects. Our results not only deepen our understanding of online fundraising dynamics but also provide a quantitative framework to disentangle the endogenous and exogenous dynamics in complex systems.
慈善众筹为遭遇意外事件（如事故、重病等）的个人和家庭提供了一个向公众寻求帮助的新渠道。因此，找到推动众筹活动筹款过程的关键决定因素至关重要，尤其是对那些身处困境的人而言。我们从一个著名的慈善众筹平台，即轻松筹，获取了一个独特的数据集，其中包含2015年10月至2020年6月期间的210,907个众筹项目，我们将揭示有多少在线捐赠是由内生性导致的，内生性指的是捐赠者通过在社交网络中进行宣传活动吸引更多人捐赠的正反馈过程。为此，我们针对每天每个众筹活动的在线捐赠事件数据校准了三种不同的霍克斯过程，这使我们能够估计分支比率，即一种内生性的度量。研究发现，在线筹款过程处于亚临界状态，近70% - 90%的在线捐赠是内生性的。此外，尽管在众筹项目创建后筹款金额、捐赠次数和捐赠者数量迅速下降，但内生性度量在众筹项目的整个生命周期内保持稳定。我们的研究结果不仅加深了我们对在线筹款动态的理解，还提供了一个定量框架来区分复杂系统中的内生和外生动向。
