Measuring reinforcer efficacy: does relative persistence do it? Comment on Meisch (2000)

R. A. Meisch (2000a) offers a new way to scale the effectiveness of reinforcers. Specifically, he uses as a measure the ratio of output under a relatively large fixed-ratio schedule to the output under a smaller fixed-ratio schedule. With such metrics, it is usually the case that as reinforcer magnitude is increased, the measured ratio increases. The method, however, violates a foundation of all measurement, comparison against a fixed standard. Some of the data provided in this article illustrate the problem of selecting what will serve as the "baseline" for comparison (i.e., what will serve as the denominator of the measure). Depending on the selection of baseline, one can find effects of a particular experimental operation ranging from none to substantial.