Table 1. The effect of being recipient of a good action on cooperation in the Prisoner's Dilemma. We used logistic regression with and without control on sex, age, and education, using ‘treat’ as a dummy variable. We report the β-value, its standard error, and the significance level. ‘Bas’ stands for ‘Baseline’, ‘Con’ for ‘Control’, and ‘Exc’ for ‘Excluded’. So, for instance, the column ‘Bas Exc vs Con 1 Exc’ reports the results of the regression using Bas Exc = 0 and Con 1 Exc = 1 as dummy variable. We find no significant effect of the dummy variable on cooperation in the PD. Being recipient of a good action does not significantly increase the probability of cooperating in the PD.

	Bas vs Con 1	Bas vs Con 1	Bas Exc vs Con 1 Exc	Bas Exc vs Con 1 Exc	Bas vs Con 2	Bas vs Con 2	Bas Exc vs Con 2 Exc	Bas Exc vs Con 2 Exc
dummy for decision
treat	−.000	.043	−.043	.022	−.405	−.419	−.370	−.382
	(.34)	(.34)	(.35)	(.36)	(.36)	(.36)	(.36)	(.37)
sex		.020		−.065		−.198		−.227
		(.35)		(.37)		(.38)		(.39)
age		−.012		−.017		−.004		−.004
		(.02)		(.02)		(.02)		(.02)
education		.291		.394*		.252		.308
		(.16)		(.16)		(.17)		(.18)
Constant	−.693**	−1.620	−.693**	−1.800	−.693**	−1.399	−.693**	−1.595
	(.24)	(.99)	(.24)	(1.04)	(.24)	(1.02)	(.24)	(1.03)
Pseudo R2	.000	.019	.000	.034	.007	.019	.006	.024
No. of cases	156	156	149	149	157	157	152	152

Significance level:

**: p < 0.01.

*: p < 0.05.