Working for Nothing: The Supply of Volunteer Labor
NBER Working Paper No. 5435
Volunteer activity is work performed without monetary recompense. This paper shows that volunteering is a sizeable economic activity in the U.S.; that volunteers have high skills and opportunity costs of time; that standard labor supply explanations of volunteering account for only a minor part of volunteer behavior; and that many volunteer only when requested to do so. This suggests that volunteering is a 'conscience good or activity' -- something that people feel morally obligated to do when asked, but which they would just as soon let someone else do.
Published: Journal of Labor Economics, Vol. 15, no. 1, part 2 (January 1997): S140-S166.