We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleModel, need, and cost effects in helping behavior.AuthorsWagner, Carl; Wheeler, LaddPublicationJournal of Personality and Social Psychology, 1969, Vol 12, Issue 2, p111ISSN0022-3514Publication typearticleDOI10.1037/h0027569