The dictator game is a popular experimental instrument in social psychology and economics, a derivative of the ultimatum game. The term "game" is a misnomer because it captures a decision by a single player: to send money to another or not. The results – most players choose to send money – evidence the role of fairness and norms in economic behavior, and undermine the assumption of narrow self-interest.
In the dictator game, the first player, "the dictator", determines how to split an endowment (such as a cash prize) between himself and the second player. The dictator's action space is complete and therefore is at his own will to determine the endowment, which means that the recipient has no influence over the outcome of the game.
While the initial game as developed by Daniel Kahneman involved third-party punishment, successors later simplified the ultimatum game to remove the punishment portion, resulting in the form now known as the dictator game. Based on homo economicus principle, one would expect players to maximize their own payoff; however, it has been shown that human populations are more “benevolent than homo economicus” and therefore rarely do the majority give nothing to the recipient.
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 do 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.
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 recipient's welfare and not only their own welfare. This is the core of the "other-regarding" preferences. A number of experiments have shown 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. Recent papers have shown that experimental subjects in the lab do not behave differently than ordinary people outside the lab regarding altruism. Studies have suggested that behavior in this game is heritable.
The idea that the highly mixed results of the dictator game prove or disprove rationality in economics is not widely accepted. Results offer both support of the classical assumptions and notable exception which have led to improved holistic economic models of behavior. Some authors have suggested that giving in the dictator game does not entail that individuals wish to maximize others' benefit (altruism). Instead they suggest that individuals have some negative utility associated with being seen as greedy, and are avoiding this judgment by the experimenter. Some experiments have been performed to test this hypothesis with mixed results.
The Trust Game is similar to the dictator game, but with an added first step. In the trust game, one participant first decides how much of an endowment to give to the second participant. The first player is also informed that whatever they send will be tripled by the experimenter. Then the second participant (now acting as a dictator) decides how much of this increased endowment to allocate to the first participant. Thus the dictator's partner must decide how much of the initial endowment to trust with the dictator (in the hopes of receiving the same amount or more in return). The experiments rarely end in the subgame perfect Nash equilibrium of "no trust". A pair of studies published in 2008 of identical and fraternal twins in the US and Sweden suggests that behavior in this game is heritable.
A variation of the dictator game called “Taking Game” (see “Experiments" section above for further detail), emerged from sociological experiments conducted in 2003, in which the dictator decides how much utility to “take” from the recipient's pre-determined endowment. This dictator game variation was designed to evaluate the idea of greed, rather than the idea of fairness or altruism generally evaluated with the standard dictator game model, also referred to as the “Giving Game”.
- Guala, Francesco; Mittone, Luigi (October 2010). "Paradigmatic experiments: The Dictator Game" (PDF). The Journal of Socio-Economics. 39 (5): 578–584. doi:10.1016/j.socec.2009.05.007.
- Bolton, Gary E.; Katok, Elena; Zwick, Rami (August 1998). "Dictator game giving: Rules of fairness versus acts of kindness". International Journal of Game Theory. 27 (2): 269–299. CiteSeerX 10.1.1.47.229. doi:10.1007/s001820050072.
- Camerer, Colin; Thaler, Richard H (May 1995). "Anomalies: Ultimatums, Dictators and Manners" (PDF). Journal of Economic Perspectives. 9 (2): 209–219. doi:10.1257/jep.9.2.209.
- Kahneman, Daniel; Knetsch, Jack L.; Thaler, Richard H. (1986). "Fairness as a Constraint on Profit Seeking: Entitlements in the Market". American Economic Review. 76 (4): 728–741. JSTOR 1806070.
- Andreoni, James; Harbaugh, William T.; Vesterlund, Lise (2008). "Altruism in Experiments". The New Palgrave Dictionary of Economics. London: Palgrave Macmillan. pp. 1–7. doi:10.1057/978-1-349-95121-5_2789-1. ISBN 978-1-349-95121-5.
- Engel, C (2011). "Dictator Games: A Meta Study". Experimental Economics. 14 (4): 583–610. doi:10.1007/s10683-011-9283-7. hdl:11858/00-001M-0000-0028-6DAA-8.
- Forsythe, Robert; Horowitz, Joel L.; Savin, N.E.; Sefton, Martin (May 1994). "Fairness in Simple Bargaining Experiments". Games and Economic Behavior. 6 (3): 347–369. doi:10.1006/game.1994.1021.
- Camerer, Colin; Loewenstein, George; Prelec, Drazen (February 2005). "Neuroeconomics: How Neuroscience Can Inform Economics". Journal of Economic Literature. 43 (1): 9–64. CiteSeerX 10.1.1.133.8842. doi:10.1257/0022051053737843.
- For an overview see Camerer, Colin F. (2011). Behavioral Game Theory: Experiments in Strategic Interaction. Princeton University Press. ISBN 9781400840885.
- Henrich, Joseph; Boyd, Robert; Bowles, Samuel; Camerer, Colin; Fehr, Ernst; Gintis, Herbert (2004). Foundations of Human Sociality: Economic Experiments and Ethnographic Evidence from Fifteen Small-Scale Societies. Oxford University Press. ISBN 9780199262045.
- Gummerum, Michaela; Hanoch, Yaniv; Keller, Monika; Parsons, Katie; Hummel, Alegra (2010-02-01). "Preschoolers' allocations in the dictator game: The role of moral emotions". Journal of Economic Psychology. 31 (1): 25–34. doi:10.1016/j.joep.2009.09.002.
- Alevy, Jonathan E.; Jeffries, Francis L.; Lu, Yonggang (2014). "Gender- and frame-specific audience effects in dictator games" (PDF). Economics Letters. 122 (1): 50–54. doi:10.1016/j.econlet.2013.10.030. ISSN 0165-1765.
- Zhang, Le; Ortmann, Andreas (2013). "The effects of the take-option in dictator-game experiments: a comment on Engel's (2011) meta-study". Experimental Economics. 17 (3): 414–420. doi:10.1007/s10683-013-9375-7. ISSN 1386-4157.
- Chowdhury, Subhasish M.; Jeon, Joo Young; Saha, Bibhas (2017). "Gender Differences in the Giving and Taking Variants of the Dictator Game" (PDF). Southern Economic Journal. 84 (2): 474–483. doi:10.1002/soej.12223. ISSN 0038-4038.
- Bhogal, M. S.; Galbraith, N.; Manktelow, K. (2016). "Physical Attractiveness and Altruism in Two Modified Dictator Games". Basic and Applied Social Psychology. 38 (4): 212–222. doi:10.1080/01973533.2016.1199382. hdl:2436/620176.
- Andreoni, James; Miller, John (2002-03-01). "Giving According to GARP: An Experimental Test of the Consistency of Preferences for Altruism". Econometrica. 70 (2): 737–753. CiteSeerX 10.1.1.165.3572. doi:10.1111/1468-0262.00302. ISSN 1468-0262.
- Eckel, Catherine C.; Grossman, Philip J. (1996-01-01). "Altruism in Anonymous Dictator Games". Rochester, NY: Social Science Research Network. SSRN 1883604. Cite journal requires
- Brañas-Garza, Pablo (2006-07-01). "Poverty in dictator games: Awakening solidarity". Journal of Economic Behavior & Organization. 60 (3): 306–320. CiteSeerX 10.1.1.378.4031. doi:10.1016/j.jebo.2004.10.005.
- Fowler, James H.; Kam, Cindy D. (2007-08-01). "Beyond the Self: Social Identity, Altruism, and Political Participation". The Journal of Politics. 69 (3): 813–827. CiteSeerX 10.1.1.165.2498. doi:10.1111/j.1468-2508.2007.00577.x. ISSN 0022-3816.
- Fowler, James H. (2006-08-01). "Altruism and Turnout". The Journal of Politics. 68 (3): 674–683. doi:10.1111/j.1468-2508.2006.00453.x. ISSN 0022-3816.
- Leider, Stephen; Möbius, Markus M.; Rosenblat, Tanya; Do, Quoc-Anh (2009-11-01). "Directed Altruism and Enforced Reciprocity in Social Networks". The Quarterly Journal of Economics. 124 (4): 1815–1851. doi:10.1162/qjec.2009.124.4.1815. ISSN 0033-5533.
- Brañas-Garza, Pablo; Cobo-Reyes, Ramón; Espinosa, María Paz; Jiménez, Natalia; Kovářík, Jaromír; Ponti, Giovanni (2010-07-01). "Altruism and social integration". Games and Economic Behavior. 69 (2): 249–257. CiteSeerX 10.1.1.688.2490. doi:10.1016/j.geb.2009.10.014.
- Exadaktylos, Filippos; Espín, Antonio M.; Brañas-Garza, Pablo (2013-02-14). "Experimental subjects are not different". Scientific Reports. 3: 1213. doi:10.1038/srep01213. ISSN 2045-2322. PMC 3572448. PMID 23429162.
- Cesarini, David; Dawes, Christopher T.; Johannesson, Magnus; Lichtenstein, Paul; Wallace, Björn (2009-01-01). "Genetic Variation in Preferences for Giving and Risk Taking". The Quarterly Journal of Economics. 124 (2): 809–842. CiteSeerX 10.1.1.638.3714. doi:10.1162/qjec.2009.124.2.809. JSTOR 40506244.
- Brañas-Garza, Pablo; Kovářík, Jaromír; Neyse, Levent (2013-04-10). "Second-to-Fourth Digit Ratio Has a Non-Monotonic Impact on Altruism". PLOS ONE. 8 (4): e60419. doi:10.1371/journal.pone.0060419. ISSN 1932-6203. PMC 3622687. PMID 23593214.
- Hoffman, Elizabeth; McCabe, Kevin; Shachat, Keith; Smith, Vernon (1994-11-01). "Preferences, Property Rights, and Anonymity in Bargaining Games" (PDF). Games and Economic Behavior. 7 (3): 346–380. doi:10.1006/game.1994.1056. hdl:10535/5743.
- Cesarini, David; Christopher T. Dawes; James H. Fowler; Magnus Johannesson; Paul Lichtenstein; Björn Wallace (11 March 2008). "Heritability of cooperative behavior in the trust game" (PDF). Proceedings of the National Academy of Sciences. 105 (10): 3721–3726. doi:10.1073/pnas.0710069105. PMC 2268795. PMID 18316737.
- Haley, K.; D. Fessler (2005). "Nobody's watching? Subtle cues affect generosity in an anonymous economic game". Evolution and Human Behavior. 26 (3): 245–256. doi:10.1016/j.evolhumbehav.2005.01.002. Concludes that people tend to be more generous if there is a picture of a pair of eyes watching them.
- Engel, C. (2011). "Dictator Games: A Meta Study". Experimental Economics. 14 (4): 583–610. doi:10.1007/s10683-011-9283-7. hdl:11858/00-001M-0000-0028-6DAA-8.
- For a recent review of the dictator game in experiments see Angela A. Stanton: Evolving Economics: Synthesis