In science in general and in the context of single-case experimental designs, replication of the effects of the intervention within and/or across participants or experiments is crucial for establishing causality and for assessing the generality of the intervention effect. Specific developments and proposals for assessing whether an effect has been…

In this reply to Baum, I emphasize that the failure to understand the processes associated with scientific verbal behavior may result in scientific statements like the generalized matching law that do not accurately reflect cause-and-effect relations.