Attracting altruists: explaining volunteer turnout during natural hazard events in Japan

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.