Do pledges lead to more volunteering? An experimental study
通过在线实验研究承诺对志愿服务的影响，发现承诺虽减少即时拒绝，但常被违背，最终志愿服务率无显著变化。
Abstract The effect of pledges on donations is ambiguous. Pledges can boost donations because pledges make it easier for people to accept a request without incurring the costs of donating right away. However, pledges can also decrease donations because individuals who pledge renege on their promises. In this paper, we study the effect of pledges on volunteering using an online experiment. We find that pledges decrease immediate rejection to volunteering requests, but pledges are often reneged later, resulting in no overall change in volunteering rates. We provide a theoretical framework for understanding the conditions under which these results emerge.