Association for Behavior Analysis International

The Association for Behavior Analysis International® (ABAI) is a nonprofit membership organization with the mission to contribute to the well-being of society by developing, enhancing, and supporting the growth and vitality of the science of behavior analysis through research, education, and practice.


38th Annual Convention; Seattle, WA; 2012

Event Details

Previous Page


Paper Session #28
Human Choice
Saturday, May 26, 2012
1:00 PM–2:20 PM
607 (Convention Center)
Area: EAB
Chair: Laurilyn Dianne Jones (The Mechner Foundation)
The Changeover Delay (COD) Decreases Behavioral Variability in Humans and in the Virtual Organism Animated by the Evolutionary Theory of Behavior Dynamics (ETBD)
Domain: Basic Research
ANDREI POPA (Emory University), Jack J. McDowell (Emory University)
Abstract: Popa and McDowell (2010) showed that the Hamming Distance, a particular mathematical feature of McDowell’s Evolutionary Theory of Behavior Dynamics (ETBD; McDowell, 2004, 2010) is computationally equivalent to the changeover delay (COD; Findley, 1954) used in experiments with live organisms. Popa and McDowell (2011) suggested that increasing the computational COD requirement reduces behavioral variability in a virtual organism animated by the ETBD. The present paper further investigated a wide range of computational COD values and used the results to formulate predictions about the effects of COD requirements on the behavioral variability of humans in concurrent-schedules environments. As predicted by ETBD, the rate of switching between alternatives was systematically decreased by increased COD requirements. These results provide further support for the ETBD as a valid account of behavior dynamics, showing that it is not only able to produce outcomes congruent with known behavior statics (the Matching Law; McDowell & Popa, 2010), but it can also formulate predictions about the behavior of live organisms. Moreover, these findings suggest that high behavioral variability may be a natural outcome of the selection pressure exerted by unstructured environments. The implications for ADHD-symptoms are discussed within the framework provided by previous research (Neuringer, 2010; Taylor et al, 2010).
Systematic Operant Bias Observed in Human Participants During Research on Choice
Domain: Basic Research
LAURILYN DIANNE JONES (The Mechner Foundation), Francis Mechner (The Mechner Foundation)
Abstract: In any research involving choice among multiple operant behaviors, the operants must be equivalent and neutral for the participants prior to the experiment, otherwise the uncontaminated effect of the independent variables cannot be determined. During a series of studies looking at the effect of number of repetitions of an operant on later choice, persistent systematic biases were observed; these could not be eradicated by varying the form of the operant. The operants used in these experiments required human participants to draw lines on a computer graphics tablet; the biases that emerged were associated with the hand motions involved in executing each operant. There were a number of learning sessions, during which participants practiced these operants different numbers of times, followed by a final “test session” in which they were required to choose between them. During the experiments the angle and length of lines drawn, spacing between lines, number of lines per operant, and the hand with which participants drew were all varied, all without elimination of operant bias; there remained persistent preferences for certain lines over others. This type of detailed quantitative analysis of bias is potentially significant for any research or applied behavior analysis that needs to assume equivalence among operant behaviors.

A Concurrent Choice Analysis of Amount-Dependent Temporal Discounting

Domain: Basic Research
JENNIFER M. KINLOCH (University of Otago), Geoff White (University of Otago)

Amount-dependent temporal discounting refers to the differential rates at which the values of large and small reinforcers are discounted over time. Most studies of temporal discounting involve the calculation of indifference points; the average point at which the choice between2 options switches, indicating indifference between the options. The present set of experiments aimed to measure strength of preference more directly. Participants were asked to indicate their strength of preference between hypothetical alternatives that differed in their monetary value, and in the delay at which they were available. Experiment 1 demonstrated temporal discounting and a magnitude effect using a direct measure of strength of preference that did not rely on the calculation of indifference points. Further analysis, using the matching law, confirmed greater sensitivity to changes in the delay when magnitudes were small than when they were large, consistent with the magnitude effect. In Experiment 2, the range of the delays were expanded to allow additional analysis and demonstrated that a hyperbolic temporal discounting curve could be fit to the data; demonstrating hyperbolic temporal discounting without the calculation of indifference points.




Back to Top
Modifed by Eddie Soh