Gary L. Cotton

Publication Date


Advisor(s) - Committee Chair

Leroy P. Metze, James R. Craig, Sam G. McFarland

Degree Program

Department of Psychology

Degree Type

Master of Arts


The purpose of this experiment was to determine whether rats’ preference to freeload (eat food pellets from a food cup) or to work for food (obtain food pellets by bar pressing) could be influenced by observing either a working or freeloading model in an adjacent operant chamber.

Following equal amounts of bar press and freeloading training, 18 male Sprague-Dawley rats approximately 100 days cold were divided into three experimental groups. The first group was permitted to view a working model while being presented a choice between bar pressing and free-loading. A second experimental group was exposed to a freeloading model while also being presented a choice between bar pressing and freeloading. A control group was permitted to make a choice between working and freeloading with no model present. Two measures of the dependent variable were taken: the ratio of the amount of food earned by bar pressing to the total amount of food consumed and the number of food pellets obtained by bar pressing.

The results of the study indicated that across testing days, there was a trend for the three groups to perform as expected. The group expose to the freeloading models earned only about one-third of its total food consumption while preferring to freeload the remainder. The group exposed to the working models preferred to earn more than half of its total food consumption via bar pressing. The total amount of food earned by the control group, predictably, fell between the amounts earned by the other two groups. The results are interpreted in terms of social facilitation.


Applied Behavior Analysis | Experimental Analysis of Behavior | Psychology