Resumen
In this paper, we apply public service motivation to the ongoing discussion of formal and informal volunteering and whether these are two distinct constructs or variations on the same theme. This exploratory research uses survey data of undergraduate students reporting their participation in both types of volunteering activities. Using structural equation modeling, these formal and informal volunteering activities show different influences on three dimensions of PSM. In addition to PSM, high school volunteering and religiosity have direct effects on rates of formal volunteering, which in turn positively influence the PSM dimensions of civic duty and self-sacrifice. Being an Evangelical Christian is associated with increased informal volunteering, which is positively related to the PSM compassion dimension. These results indicate that the different dimensions of PSM, and how formal and informal volunteering influences them, should be useful tools for scholars and practitioners seeking to understand these distinct types of pro-social behaviors.