Generalizing the Effect of Extreme Outcomes in Risky Decision Making: A Cross Species Comparison of Pigeons and Humans

  • Author / Creator
    Pisklak, Jeffrey M
  • Research has shown that when decisions between risky and fixed options are based on repeated exposure to the governing contingencies, preference is often influenced by an overweighting of the most extreme outcomes appearing in the decision context. Known formally as the extreme-outcome rule, this predicts that organisms will be more risk seeking for gains relative to losses. This thesis examines the extent to which the extreme-outcome rule can be considered to generalize both within and across two evolutionary distant species: pigeons (Columba livia) and humans (Homo sapiens). In Chapter 2, an operant chamber analogue of a foraging task was conducted with pigeons and humans to test the predictions of the extreme-outcome rule. Risk-preference results across both species corresponded to the predictions of the extreme-outcome rule; however, a detailed analysis suggested that the risk-preference results might be confounded by an effect of probabilistic discounting. Controlling for this, Chapter 3 re- examined the predictions of the extreme-outcome rule. Pigeons showed no effect of overweighting the most extreme values. Humans who passed the catch trials did show a clear effect of extreme-outcomes; though, this only represented approximately half of the sample tested, as the other half failed to meet the set passing criteria for catch trial performance. Further testing revealed that this poor performance was likely the result of poor instructional (i.e., discriminative) control.

  • Subjects / Keywords
  • Graduation date
    Spring 2016
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
  • Supervisor / co-supervisor and their department(s)
  • Examining committee members and their departments
    • Spetch, Marcia (Psychology)
    • Chapman, Craig (Physical Education and Recreation)
    • Hurd, Pete (Psychology)
    • Sturdy, Christopher (Psychology)