Well-Being and Altruism Per Capita Donation Rates Well-Being Scores (3 time p separate regressions with and without the inclusion of the test showed that subjective well-being mediated the 11,201 Well-Being and Altruism 5 2010 predicted rates of altruistic donations during that time period, β = 0.33, t(47) = 2.61, p = .012. We estimated separate regressions with and without the inclusion of our hypothesized mediator (well-being) and conducted a Sobel test; consistent with the engine model, results of the test showed that subjective well-being mediated the Quintiles 1 2 3 4 5 Per Capita Donation Rates Quintiles 1 2 3 4 5 Well-Being Scores Fig. 1. Per capita altruistic living kidney donation rates (1999–2010) and 2010 Gallup-Health￾ways Well-Being Index scores across states. Data on kidney-donation rates were drawn from the Organ Procurement and Transplantation Network (2011); Well-Being Index scores were drawn from Gallup (2012). Quintile 1 represents the highest well-being/altruistic donation rates. Downloaded from pss.sagepub.com by Cai Xing on February 11, 2014