Discussion Papers 745
5 Experimental results
cance).5 The average profit in team remuneration is significantly below the optimal profit of
250 (Wilcoxon test) and not significantly different from the equilibrium profit of 187.5.
In the VOLUNTARY ASYM treatment, the average team effort of the low-cost players is 34.51
(standard deviation of 11.09), while the average team effort of the high-cost players is 30.14
(standard deviation of 8.01).6 Both effort levels are significantly above the respective domi-
nant strategy of 20 or 16 (binomial test, 1-percent significance). Requiring significance at the
10-percent level (Wilcoxon test), both effort levels are not significantly different from the
Pareto optimum of 40 and 32, respectively. Furthermore, neither the low-cost players’ avera-
ge effort nor its standard deviation is significantly different from the respective value of the
high-cost players (Wilcoxon test).
The resulting average profit of the low-cost players (127.26, standard deviation of 74.05) is
not significantly different from the one of the high-cost players (137.1, standard deviation of
59.85) in team remuneration (Wilcoxon test).7 While the high-cost players’ average profit is
significantly above their equilibrium profit (Wilcoxon test, 5-percent significance), the low-
cost players’ average profit is not significantly different from their equilibrium profit (Wil-
coxon test). Both low-cost and high-cost players’ profits are not significantly different from
their respective joint profit-maximizing profit (Wilcoxon test): the low-cost players realize 99
percent and the high-cost players realize 86 percent of it.
The high-cost players’ average profit is significantly higher in team remuneration than in
private remuneration, where it is 68.06 (Wilcoxon test, 2-percent significance). The low-cost
players’ average profit is in six of the eight groups higher in team remuneration than in priva-
te remuneration. However, this difference is statistically not significant (Wilcoxon test). The
low-cost players’ profit under private remuneration is 112.89 on average.
5 We observe no significant increase or decrease of profit from the first set of 15 periods to the last set of 15
periods, neither in team nor in private remuneration. The standard deviation, however, decreases from 165.34 to
81.31 in team remuneration (Wilcoxon test, 10-percent significance) and from 51.89 to 22.25 in private remunera-
tion (Wilcoxon, 5-percent significance).
6 Comparing the average team effort in the first set of 15 periods to that in the final set of 15 periods, we observe
a decrease both for the low-cost and the high-cost players. Neither is statistically significant (Wilcoxon test) al-
though the decrease of the low-cost players’ effort just fails significance.
7 The profit of the low-cost players tends to increase from the first set of 15 periods to the last set of 15 periods
under team remuneration (Wilcoxon test, 5-percent significance). The profit of the high-cost players shows no
tendency to increase or decrease under team remuneration (Wilcoxon test).
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