Much or More? Experiments of Rationality and Spite with School Children

There are many ways to be competitive (as there are many ways to be cooperative, too). The most studied one, both theoretically and empirically, is called "rationality" (maximization of self-interest). The term rationality traditionally refers to individuals acting towards the maximization of their own selfish interests, measured by the "pay-off" concept originally introduced in game theory (Neumann, & Morgenstern, 2004; Tversky, Kahneman, 1986). In a sense, one compares his/her fate in all possible scenarios and chooses the best possible outcome. However, in most real situations of experimental interest, people compete against each other. Taking as an example an experimental game, where each of two individuals has two strategic possibilities and pay-off functions associated with all possible combinations, a simple maximization of one's pay-off says nothing about the effect of this decision to the direct competitor's pay-off. If a strategic decision maximizes one's pay-off but results in an even higher pay-off for the opponent, then this may be a wrong decision in an environment of direct competition. In fact, mathematical models along these lines are considered the starting point of the studies of cooperation, as the benefit of one is also a benefit for the other (Chalub, Santos, Pacheco, 2006; Falk, Fehr, & Fischbacher, 2005; Hamilton, 1970; Leimar, & Hammerstein, 2001; Santos, & Pacheco, 2005; Santos, Pacheco, & Lenaerts, 2006; Trivers, 1971). Evolutionary psychology has further explored this by studying the impact that neurological and emotional processes related to altruism and cooperation have on the survival and spread of individuals (Van Lange, 1999; Van Lange, Agnew, Harinck, & Steemers, 1997; de Wall, 1996). Defined as an act that causes loss of payoff (or any other type of cost) to the opponent, spite may be advantageous in a competitive scenario given certain precise conditions. We will not specify here the full set of conditions that make spite advantageous; we stress however, that rationality (maximization of own's payoff) and spite (minimization of other's payoff) are not mutually exclusive. Humans display many behaviors that could be classified as spiteful and spite is often linked with negative emotional responses to inequity such as envy and jealousy (Berke, 1988; Dufwenberg, & Guth 2000; Salovey, & Rothman 1991; Smith, 1991). Although apparently maladaptive, these behaviors are suited to certain competitive contexts. By comparing payoffs directly with another individual, one could be empowered with the means of assessing the best strategy for obtaining a payoff. Some authors have suggested that this would elicit an "outcompete your neighbor" decision process that would allow exerting just the right amount of effort to succeed in outcompeting rivals (Hill & Buss, 2008). In economics, the process of dumping (where a firm decreases the price of its product, possibly below cost price, intending to drive competitors out of the market) is such an example (Winters, 1991). Humans also commonly display what is known as "last-place aversion." In this case individuals prefer to minimize the probability of being last (for example, in a ranking of income distribution), rather than maximizing their own pay-off (Kuziemko, Buell, Reich, & Norton, 2011). Spiteful behavior has also been identified in a study where higher-ranking individuals are more likely to spite lower ranking individuals than their similars (Fehr, Hoff & Kshetramade 2008). For this study, the starting point was to understand if the propensity for spiteful behavior was present in children along with the propensity for rationality, or if children displayed these propensities at different stages of their development, ultimately comparing the motivations and the ability of children and teenagers to react to stimuli that induced behavior in one or the other direction. Namely, we wanted to quantify, according to age, the propensity for acting rationally or spitefully. …