Note on Methodology in Comparative Behavioral Analysis: Systematic Variation vs Control by Equation

Abstract

In the search for methodologies that yield meaningful interspecies performance differences over the greatest taxonomic range, serial discrimination reversal has demonstrated the greatest promise. However, interpretation of the obtained differences in performance is complicated by a possible mismatching of procedural variables, such as motivational or incentive levels, across species. In short, differences in performance across species may merely reflect unequal motivation, incentive, and the like, and not some more basic organismic, phyletic or taxonomic variable. Two alternative solutions to this methodological dilemma, systematic variation and control by equation, are discussed in view of recent research. Evidence supporting control by equation is presented. The necessity for taxonomic calibration of procedural variables is illustrated.