The lower pen, which we call the event pen, records the onset and offset of experiment–defined events by going up one step after which it can only go back down one step. As the paper unrolls, this pen marks a line at two slightly different levels according to whether it has moved up or moved down its one allowed step.
Given a whole, functioning physiology—an organism—behavior occurs, because eliciting, evocative, or other stimuli occur. The functionally related combination of behaviors and stimuli makes up contingencies. Occasionally a contingency occurs alone, but more often two or more contingencies operate at the same time, and researchers have called these concurrent contingencies.
In considering multiple–baseline designs, an example from an actual study using one of the multiple–baseline forms would help. The value of this example, which involves the behavior–based form, also resides in two of its other characteristics.
As early behaviorological practitioners adapted ABAB/Reversal designs to applied settings, they faced increasingly complex applied situations requiring more sophisticated single–subject experimental designs. For example, sometimes the repetition of Baseline or Intervention phases would stand out as unethical or otherwise not possible.
In 1975 David Anderson and I worked on an applied study at the University of Queensland in Brisbane, Australia, which was when and where I began my college teaching career. This study contains some uncommon features worthy of attention, features that one would usually only find spread across several studies.
After considering the ABAB/Reversal type of single–subject designs for basic experimental research in a recent column, this column turns to similar designs for applied research and practice. In applied settings, research considerations differ from laboratory settings, and some compel the adoption of the more complicated “multiple–baseline” single–subject designs that a later column covers.
The first several decades of experimental behavior science occurred from the 1930s through the 1950s. During this time Skinner, his colleagues in the natural science of behavior, and their students (i.e., the predecessors of today’s behaviorologists) gradually built the foundations of their behaviorological science mostly through the kinds of basic laboratory methodologies that we covered in the last column.
Disciplinary contingencies compelled the use of single–subject experimental designs throughout the history of natural behavior science. This started with the experimental preparations of Skinner’s early laboratory at Harvard in the 1930s and continues up through today’s laboratory and applied research efforts.
So, how does the natural science of behavior make discoveries? How does it apply those discoveries to bring practical benefits to people? What experimental equipment and methods does it employ in its basic and applied research? The next several columns consider the answers to these questions in terms of the standard research equipment and procedures of both the classic behavior–research laboratory and the practical research for applied settings and interventions.
