Social influences in giving: Field experiments in public radio

Academics from multiple disciplines, as well as nonprofit practitioners, have examined the internal motivations of individuals to make chari-table contributions and voluntarily provide public goods. These scholars include economists (e.g., Kolm & Ythier, 2006; Powell & Steinberg, 2006), psychologists (e.g., Batson, 1990; Carlson, Charlin, & Miller, 1988; Clary, Snyder, Ridge, Copeland, Stukas, Haugen, & Miene, 1998; Penner, Dovidio, Piliavin, & Schroeder, 2005; Piaget, 1932; Weber, Kopelman, & Messick, 2004), sociologists (e.g., Havens, O’Herlihy, & Schervish, 2006), and nonprofit marketing and management scholars (e.g., Bennett & Sargeant, 2005). In economics, models of altruism (e.g., Becker, 1974), impure and warm-glow altruism (e.g., Andreoni, 1989, 1990), conditional cooperation (e.g., Fischbacher, Gachter, & Fehr, 2001), and reciprocity (e.g., Sugden, 1984) have been developed and tested in the experimental laboratory (e.g., Croson, 2007).