In 1988, a group of researchers at the University of Iowa conducted a controlled experiment to evaluate the homo economicus model of behavior with groups of voluntarily recruited economics, accounting, and business students. These experimental results contradict the homo economicus model, suggesting that players in the dictator role take fairness and potential adverse consequences into account when making decisions about how much utility to give the recipient. A later study in neuroscience further challenged the homo economicus model, suggesting that various cognitive differences among humans affect decision-making processes, and thus ideas of fairness. Experimental results have indicated that adults often allocate money to the recipients, reducing the amount of money the dictator receives. These results appear robust: for example, Henrich et al. discovered in a wide cross-cultural study that dictators allocate a non-zero share of the endowment to the recipient. In modified versions of the dictator game, children also tend to allocate some of a resource to a recipient and most five-year-olds share at least half of their goods. A number of studies have examined
psychological framing of the dictator game with a version called "taking" in which the player "takes" resources from the recipient's predetermined endowment, rather than choosing the amount to "give". Some studies show no effect between male and female players, but one 2017 study reported a difference between male and female players in the taking frame, with females allocating significantly more to the recipient under the "taking" frame compared to the "giving" frame, while males showed exactly the opposite behavior – nullifying the overall effect. In 2016, Bhogal et al. conducted a study to evaluate the effects of perceived attractiveness on decision-making behavior and altruism in the standard dictator game, testing theories that altruism may serve as a courtship display. This study found no relationship between attractiveness and altruism. If these experiments appropriately reflect individuals' preferences outside of the laboratory, these results appear to demonstrate that either: • Dictators'
utility functions include only money that they receive and dictators fail to maximize it. • Dictators' utility functions may include non-tangible harms they incur (for example
self-image or anticipated negative views of others in society), or • Dictators' utility functions may include benefits received by others. Additional experiments have shown that subjects maintain a high degree of consistency across multiple versions of the dictator game in which the cost of giving varies. This suggests that dictator game behavior is well approximated by a model in which dictators maximize utility functions that include benefits received by others, that is, subjects are increasing their utility when they pass money to the recipients. The latter implies they are maximizing a utility function that incorporates the recipient's welfare and not only their own welfare. This is the core of the "other-regarding" preferences. A number of experiments have shown that donations are substantially larger when the dictators are aware of the recipient's need of the money. Other experiments have shown a relationship between
political participation, social integration, and dictator game giving, suggesting that it may be an externally valid indicator of concern for the well-being of others. Regarding altruism, recent papers have shown that experimental subjects in a lab environment do not behave differently to other participants in an outside setting. Studies have suggested that behavior in this game is heritable. ==Challenges==