title: Fairness norms and theory of mind in an ultimatum game: judgments, offers, and decisions in school-aged children.
abstract: The sensitivity to fairness undergoes relevant changes across development. Whether such changes depend on primary inequity aversion or on sensitivity to a social norm of fairness is still debated. Using a modified version of the Ultimatum Game that creates informational asymmetries between Proposer and Responder, a previous study showed that both perceptions of fairness and fair behavior depend upon normative expectations, i.e., beliefs about what others expect one should do in a specific situation. Individuals tend to comply with the norm when risking sanctions, but disregard the norm when violations are undetectable. Using the same methodology with children aged 8-10 years, the present study shows that children's beliefs and behaviors differ from what is observed in adults. Playing as Proposers, children show a self-serving bias only when there is a clear informational asymmetry. Playing as Responders, they show a remarkable discrepancy between their normative judgment about fair procedures (a coin toss to determine the offer) and their behavior (rejection of an unfair offer derived from the coin toss), supporting the existence of an outcome bias effect. Finally, our results reveal no influence of theory of mind on children's decision-making behavior.
authors.affiliation: Research Unit on Theory of Mind, Department of Psychology, Università Cattolica del Sacro Cuore, Milano, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Castelli
authors.affiliation: Research Unit on Theory of Mind, Department of Psychology, Università Cattolica del Sacro Cuore, Milano, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Massaro
authors.affiliation: Behavioral Ethics Lab, Departments of Philosophy and Psychology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Cristina
authors.initials: C
authors.lastname: Bicchieri
authors.affiliation: Department of Psychology, University of Michigan, Ann Arbor, Michigan, United States of America.
authors.forename: Alex
authors.initials: A
authors.lastname: Chavez
authors.affiliation: Research Unit on Theory of Mind, Department of Psychology, Università Cattolica del Sacro Cuore, Milano, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Marchetti
mesh_terms: D000328:Adult; D002648:Child; D003657:Decision Making; D005260:Female; D005717:Games, Experimental; D006801:Humans; D007600:Judgment; D008297:Male; D012919:Social Behavior; D056345:Theory of Mind