title: Interactions, trends, and the search for order.
authors.affiliation: Experimental Education Unit, University of Washington, Seattle 98195.
authors.forename: F F
authors.initials: FF
authors.lastname: Billingsley
mesh_terms: D000293:Adolescent; D001521:Behavior Therapy / Q000379:methods*; D002648:Child; D003216:Conditioning, Operant; D004495:Education of Persons with Intellectual Disabilities; D006801:Humans; D009042:Motivation; D012054:Reinforcement, Psychology; D012931:Social Environment