Document Type



Two experiments were conducted to study stimulus
equivalence as a function of class size and number of classes. In
the first experiment, equivalence was tested in 50 normal adult
subjects following a linear series training structure. Subjects were
successively assigned to either of 10 groups, exposed to a specific
stimulus material. For subjects in which number of classes
increased, up to six, B-stimuli served as pictures, while A-, and Cstimuli
were Greek letters, and "equivalence" was tested in CA
tests. The A-, B-, and C-stimuli were the same for all subjects in
whom class members increased up to six, where D-, E- and Fstimuli
were Greek letters. FOllowing AB, BC, CD, DE, and FE
training, FA, EA, FB, FC, EB, DA, FD, EC, DB, and CA
"equivalence" tests were run. In the second experiment, a manyto-
one training structure was used to study equivalence as a
function of increasing class size without increase number of
nodes. The results indicate that the probability of equivalence
decreased more as function the number of nodes than as a
function of number of classes. Reaction times, particularly to the
comparison stimuli, generally increased initially during tests,
possibly indicating precurrent problem solving behavior prior to the
response to a comparison stimulus.