Intermediaries in Trust: Indirect Reciprocity, Incentives, and Norms

Table 1

Overview of Experiments 1 and 2 results. The AR/FR column presents the ratio between the corresponding results in the alternating and the fixed role experiment. The last two columns present Wilcoxon rank sum tests of the null hypothesis that the result distribution is the same in the two experiments.

Treatment		Altern. roles		Fixed roles		AR/FR	Wilcoxon
		Mean	SE	Mean	SE
Baseline	A investments	3.22	0.16	3.07	0.16	1.05	207.5	0.385
	B returns	2.00	0.16	3.54	0.26	0.56	142.5	0.079
	B ret. (prop.)	0.09	0.01	0.16	0.01	0.56	137.0	0.059
	CI	0.50	0.00	0.51	0.00	0.98	319.0	0.118
No incentive	A investments	5.07	0.23	3.47	0.12	1.46	174.0	0.029
	B returns	6.87	0.42	3.24	0.16	2.12	196.0	0.003
	B ret. (prop.)	0.24	0.01	0.14	0.01	1.71	189.0	0.006
	CI	0.63	0.01	0.54	0.00	1.17	396.0	0.000
Fixed inc.	A investments	3.61	0.21	2.36	0.11	1.53	170.0	0.040
	B returns	3.75	0.30	2.47	0.15	1.52	142.0	0.232
	B ret. (prop.)	0.17	0.01	0.10	0.01	1.70	150.0	0.153
	CI	0.54	0.01	0.52	0.00	1.04	264.0	0.319
A incentive	A investments	5.21	0.21	3.96	0.14	1.32	174.5	0.028
	B returns	6.42	0.45	5.27	0.27	1.22	147.0	0.180
	B ret. (prop.)	0.23	0.01	0.21	0.01	1.10	134.0	0.333
	CI	0.60	0.01	0.56	0.01	1.07	365.0	0.002
B incentive	A investments	4.50	0.18	3.68	0.14	1.22	154.0	0.121
	B returns	4.75	0.28	4.07	0.19	1.17	141.5	0.238
	B ret. (prop.)	0.19	0.01	0.18	0.01	1.06	130.0	0.387
	CI	0.58	0.01	0.55	0.00	1.05	307.0	0.071