The Psychological Record

, Volume 67, Issue 1, pp 11–25 | Cite as

A Risk-Reduction Model of Sharing: Role of Social Stimuli and Inequity

  • Stephanie Jimenez
  • Cynthia Pietras
Original Article


The present study experimentally investigated human cooperation (sharing) in a laboratory foraging task that simulated environmental variability and resource scarcity (shortfall risk). Specifically, it investigated whether a risk-reduction model of food sharing derived from the energy budget rule could predict human cooperative behavior. Participants responded on a computer task for money and were given the choice between working alone or working with others and pooling earnings. Earnings could be kept only if the sum exceeded an earnings requirement (i.e., a need level). The effects of social variables on sharing were investigated to determine whether they constrained optimal decision making. The experiments investigated choice when participants were told the partner was a computer or a (fictitious) partner (Experiment 1) and when the earnings between the participant and partner were inequitable (Experiment 2). The results showed that social variables had no effect on decision making. Instead, sharing patterns were in accord with predictions of the risk-reduction model. These results provide additional evidence that a risk-reduction model of food sharing derived from risk-sensitive foraging models may be useful for predicting human cooperation for monetary outcomes.


Sharing Risk-sensitive foraging Energy-budget Cooperation Risk reduction 



This research was part of a doctoral dissertation by the first author and was supported by a Graduate Student Research Fund provided by the Graduate College at Western Michigan University. We would like to thank Alan Poling, Scott Gaynor, and Maarten Vonhof for their invaluable suggestions and comments and Zachary Zimmerman for his assistance with this research. Portions of these data were presented at the annual Association for Behavior Analysis International convention, Minneapolis, MN, May 2013.

Compliance with Ethical Standards


This study was funded by a Graduate Student Research Fund provided by the Graduate College at Western Michigan University.

Conflict of Interest

Dr. Stephanie Jimenez and Dr. Cynthia Pietras both declare that they have no conflicts of interest.

Ethical Approval

All procedures were in accordance with the ethical standards of the institutional and/or national committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Association for Behavior Analysis International 2016

Authors and Affiliations

  1. 1.Department of PsychologyUniversity of Pittsburgh at JohnstownJohnstownUSA
  2. 2.Western Michigan UniversityKalamazooUSA

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