Stationary distribution of moral strategies in a population

Abstract

ORCIDs 0000-0001-8567-7931 (J.v.B.) 0000-0002-6621-8120 (L.C.) AbstractEvolutionary models show that human cooperation can arise through direct reciprocity relationships.However, it remains largely unclear which psychological mechanisms may proximally motivate an individual to reciprocate. Recent evidence demonstrates that psychological motives for reciprocal choices (i.e., moral strategies) differ between individuals, which raises the question whether these differences have a stationary distribution in a population or are rather an artifact of the experimental task. Here, we combine data from three independent studies and participant samples to find that the relative prevalence of different moral strategies is highly stable across these datasets. Furthermore, the distribution of moral strategies is relatively unaffected by changes to the salient features of the experimental paradigm. Finally, the moral strategy classification assigned by our computational modeling analysis corresponds to the participants' own subjective experience of their psychological decision process, and no existing models of social preference can account for the observed individual differences in moral strategies. This research supports the view that social decision-making is not just regulated by individual differences in 'pro-social' versus 'pro-self' tendencies, but also by trait-like differences across several alternative pro-social motives, whose distribution in a population is stationary.

Moral strategies and psychopathic traits.

“…Our modified version of the MSM is the first to additionally include generosity as a possible moral strategy. The distribution of the other moral strategies in the current sample is comparable with previous findings from a study that used the MSM in healthy adults (van Baar et al, 2019, 2020).…”

“…Our computational model yields motive-specific parameters that allows us to index the strength of a participant's inclination toward using a particular moral strategy such as guilt aversion (GA) and inequity aversion (IA). Prior studies that implemented this model identified four moral strategies: Inequity aversion, guilt aversion, moral opportunism, and greed (van Baar et al, 2019(van Baar et al, , 2020. To examine the construct validity of these strategies, van Baar et al (2020) asked participants to indicate their decision strategy through self-report.…”

“…Prior studies that implemented this model identified four moral strategies: Inequity aversion, guilt aversion, moral opportunism, and greed (van Baar et al, 2019(van Baar et al, , 2020. To examine the construct validity of these strategies, van Baar et al (2020) asked participants to indicate their decision strategy through self-report. The results demonstrated that each of the moral strategies captured by this particular computational model could be identified in multiple independent samples, and that the model-based strategies were well-aligned with participants' own perception of the decision strategy she/he used.…”

Latent motives guide structure learning during adaptive social choice

“…This intimates that many strategic socio-economic behaviors that rely on predictions about others' future choices in novel contexts, such as competitive bargaining 45 , market entry 46,47 , and collective action 2,33,48,49 , are scaffolded by a motive-based structure learning mechanism. Given that social motives (e.g., greed) vary between individuals in the population 10,12,14,15,50 , effective inference of these motives in others is likely instrumental in achieving competitive and collaborative goals.…”

“…Here, we examine the possibility that motives, such as greed 5 , inequity aversion 6,7 , and risk aversion 8,9 , form the building blocks of these mental models of others' behavior. Motives are plausible components of such models because they can predict behavior across contexts 10 , differ reliably between people [11][12][13][14][15] , and are inferred from an early age [16][17][18] . Studies of action understanding suggest that people can infer another's motives by observing their actions 19 .…”