Volunteers play a crucial role in post-disaster situations, providing resources, emotional support, and labour when local and national government capacity may be diminished. The number of volunteers who assist can range from dozens to more than one million. Yet, little is known about the broader conditions that result in more (or fewer) of them heading to disaster sites. Using a new dataset of 57 disasters in Japan between 1995 and 2019, this study analyses the factors influencing volunteer turnout. Controlling for a number of aspects, three are found to correlate most strongly: the number of dead and missing; the size of the population affected by the shock; and the time period of the year. Moving beyond tables of regression coefficients, simulations and graphics are used to illustrate the relationship between key variables of interest as well as uncertainty about the predictions. The study's findings—robust across multiple model types—have important policy and practical implications.

中文翻译：

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吸引利他主义者：解释日本自然灾害事件期间的志愿者投票率

当地方和国家政府的能力可能减弱时，志愿者在灾后情况下发挥着至关重要的作用，提供资源、情感支持和劳动力。提供帮助的志愿者人数可以从几十人到超过一百万不等。然而，对于导致更多（或更少）他们前往灾难现场的更广泛的条件知之甚少。本研究使用 1995 年至 2019 年日本 57 次灾害的新数据集，分析了影响志愿者投票率的因素。控制多个方面，发现三个相关性最强：死亡人数和失踪人数；受冲击影响的人口规模；和一年中的时间段。超越回归系数表，模拟和图形用于说明关键变量之间的关系以及预测的不确定性。该研究的结果——在多种模型类型中都很稳健——具有重要的政策和实际意义。