Institutions and investors alike have often been confronted with the question of which individuals are most eligible for the distribution of endowments. Here, we consider the Ultimatum game in a spatial setting and propose a hierarchy of interference mechanisms based upon the amount of information available to an external decision-maker and desired standards of fairness. Starting from previous findings on the spatial Prisoner’s Dilemma, we explore the differences arising from targeting different roles, but also the effects of mutation and stochasticity. Our key findings show that macroscopic monitoring of the population requires thorough information-gathering and that local observations can mediate this requirement. Moreover, we discuss the circumstances in which fair behaviour should be fostered in order to reduce unnecessary spending. Finally, we present our suggestions for promoting fairness as an external decision-maker when asymmetric roles in interactions can be targeted.
