variables DO is close to zero and highly insignificant, while the coefficient of DA is significant both
statistically and economically, indicating an 8% increase in productivity compared to the control
group due to action-oriented altruism. Also, the analysis disaggregated by gender confirms the
picture already drawn by the non-parametric tests: in the case of women productivity is increasing
by 14% due to action-oriented altruism, while for men the coefficient of DA is close to zero and
highly insignificant. Very similar results (not reported) are obtained when using M estimation
(iteratively reweighted least squares15).
Table 3 - |
Median Regression | ||
All |
Men |
Women | |
DA |
.078** |
.027 |
.139** |
(.039) |
(.092) |
(.060) | |
DO |
-.007 |
-.061 |
-.034 |
(.035) |
(.085) |
(.056) | |
Constant |
.088*** |
.111 |
.088** |
(.029) |
(.073) |
(.043) | |
N. |
71 |
33 |
38 |
Standard errors in parentheses. *** [**] (*) denote significance at 1, |
[5], (10) % level. |
4 Concluding Remarks
Experimental methods have enhanced our understanding of how various behavioral notions, such
as fairness, trust, reciprocity, loss-aversion and peer effects operate in labor markets (Falk and
Gaechter, 2008). Recently there has been an increased interest in understanding the motivating
factors behind workers’ pro-social behavior in workplace settings. This paper contributes to this
literature by performing a first, to our knowledge, field experiment which attempts to disentangle
and measure the two alternative sources of workers’ pro-social motivation. Our results underline the
importance of action-oriented intrinsic motivation in the workplace, as it accounts for an increase
in effort provision that is both statistically and economically significant. On the other hand, we do
not find any evidence of output-oriented motivation.
One might think that another motivation that may be responsible for the students’ response
15In particular, we use the STATA implementation, rreg, which uses Huber weights at the beginning of the com-
putation and biweights successively.
11