Two students with moderate to severe mental retardation learned delayed matching to sample in which some of the trials involved complex sample stimuli, each consisting of a picture and a printed word. Matching to either the preceding picture or printed word sample was reinforced. Evidence for the formation of equivalence classes was observed.…

This study examined the matching and sequencing of quantities, numerals, and arbitrary forms by two individuals with mental retardation. Results showed that sequence training did not readily lead to new matching performances, unlike prior research with college students. Instead, training in matching to sample yielded emergent sequence production…