Date of Award


Degree Name

Master of Arts



First Advisor

Dr. Cynthia J. Pietras

Second Advisor

Dr. Lisa E. Baker

Third Advisor

Dr. Mark P. Alavosius

Access Setting

Masters Thesis-Open Access


Three experiments using a parametric, single-subject design investigated gambling behavior in eight adult humans on a slot-machine simulation. Participants were staked with credits exchangeable for money prior to each session. Experiment 1 a was a systematic replication of Weatherly and Brandt (2004), which investigated the effects of percentage payback (the amount of money gained as a proportion of the amount of money bet) on gambling. Percentage payback was varied from 50% to 110% across conditions. Consistent with Weatherly and Brandt, gambling did not vary systematically across percentage-payback conditions. Experiment 1 b replicated Experiment 1 a but also included forced-exposure sessions prior to experimental sessions to guarantee a minimal exposure to the percentage-payback conditions. The results were similar to Experiment 1 a. In Experiment 2, win probability and size were manipulated across conditions. Only one of three participants showed sensitivity to this manipulation. In all experiments, most participants tended to place fewer bets as the experiment progressed. Most participants reported the use of a gambling strategy that was consistent with their performance on the gambling task. Overall, these results highlight the utility of studying gambling with procedures that give participants extensive experience with gambling conditions.

Included in

Psychology Commons