A Note on “Behavioral Limits”
The purpose of this methodological note is to emphasize that an experimental psychologist is often implicitly interested in behavior in some fixed condition as the limit of behavior in a sequence of conditions and to assert that it is possible to design experiments with this as a goal. When a psychologist fits a function or develops a theoretical function to describe a set of points, any point included, and in particular the end points, can be looked upon as achieving much of their significance from the values of the sequence of points "approaching" them. Such a purpose can, however, be more explicitly incorporated. Behavior in a sequence of conditions can be expressly used to interpret the behavior in, o r isolate the variables necessary to predict the behavior in, a "limiting" condition of particular interest. In this way, behavior at a fixed value of a variable may be studied (and implicitly is studied) in much the same way mathematicians found it useful to study the behavior of a function at a point. A cause of some difficulties is thar the original source of many experimental paradigms currently used in experimental psychology is experimental agriculture. Along with statistical methods, e.g., the analysis of variance, which infiltrated psychology were some extra statistical influences which have acted essentially as restraints against explicitly interpreting the resulcs at one point in terms of the results for other values of a variable. These restraints have often resulted in an even distribution of interest over the range of variables, but in experimental psychology, there is no strong analogy to evenly divided plots of ground. Even counterbalancing methods which rely implicitly upon this analogy also impose restrainrs on concenrrating interest at a particular point. It therefore appears that as experimental psychology becomes more interested in finegrained relationships, such restraints in the design of experiments must be avoided. Some investigation of behavioral limits, which represent an extreme in concentration of interest, can be conducted within existing experimental paradigms. In an experiment by McConnell and Shelly (1960) an effort was made to obtain some insights into continuous tracking behavior through examining how behavior changed on a series of discrete tracking problems which approached the continuous case. Here it was found thar the same method ( a linear relationship on amplitude of step inputs) could be used for predicting tracking performance on two quite different continuous tasks, thus showing that they, as limits of similar sequences of conditions, had more similar properties than their apparent dissimilarity indicates. The benefits which accrue from this type of study will, however, never be fully exploited without the development of statistical methods explicitly designed to treat certain results as behavioral limits.