ABSTRACT
More or less, except for Ayllon and Michael, the author behavior analysts hadn’t yet figured out how to cope with single-subject studies, where each little study was somewhat different from the others, not exact replications. Shreeya had no language, not even speech sounds. In fact, all she did was squeal, not as an effort to talk, but just as a form of self-stimulation, like the people singing in the shower. The common mistake is to look in the direction the people wanted her to go, or make a sort of come-here sign when they wanted her to come here, or make a patting-the-chair sign when the people wanted her to sit down. Most behavior analysts say a set of arbitrary, symbolic stimuli has formed an equivalence class if all stimuli in that set have reflexive, symmetrical, and transitive relations (e.g., Mark’s written and spoken name and his photo).
