Multiple Exemplar Training: Some Strengths and Limitations.

In successful multiple exemplar training, a set of exemplars that sample the range of stimulus and response topographies is trained, and the full range of performances results. Examples abound in experimental psychology and include abstraction and concept learning, responding to relations, identity matching, rule following, behavioral variability, responding to wh-questions, describing past events, learning sets, and continuous repertoires. Thus, behavior analysts often allude to a history of multiple exemplar training to account for different generalized performances. It is easy to see how a strategy of multiple exemplar training can work with many types of performances, even performances that involve relations between objects or events. However, there appear to be at least two exceptions, where direct multiple exemplar training does not work well: (1) when there are no physical dimensions at all along which generalized performances can emerge, and (2) when the relation between a stimulus and an effective response is complex. Interpretation of the latter type of cases in terms of mediated generalization is outlined and discussed. An experimental and conceptual research program should produce an account of the general limits of multiple exemplar training, and guidelines for the most effective training for generalized skills.

Intensive Quality Assurance of Therapist Adherence to Behavioral Interventions for Adolescent Substance Use Problems.

This study was a crosscultural replication of a study that investigated therapist adherence to behavioral interventions as a result of an intensive quality assurance system which was integrated into Multisystemic Therapy. Thirty-three therapists and eight supervisors participated in the study and were block randomized to either an Intensive Quality Assurance or a Workshop Only condition. Twenty-one of these therapists treated 41 cannabis-abusing adolescents and their families. Therapist adherence and youth drug screens were collected during a five-month baseline period prior to the workshop on contingency management and during 12 months post workshop. The results replicated the previous finding that therapist adherence to the cognitive-behavioral interventions, but not to contingency management, showed a strong positive difference in trend in favor of the intensive quality assurance condition. While the clinical impact of such quality assurance may be delayed and remains to be demonstrated, cannabis abstinence increased as a function of time in therapy, and was more likely with stronger therapy adherence to contingency management, but did not differ across quality assurance interventions.

A retrospective 60-year review of Murray Sidman's Tactics of Scientific Research and some of its influence on behavior analysis.

Murray Sidman's book, Tactics of Scientific Research: Evaluating Experimental Data in Psychology, published in 1960, has been called the bible of the experimental analysis of behavior and has been a major influence on basic as well as applied research in behavior analysis. The contents of the early reviews of the book are summarized and the commemoration in The Behavior Analyst at the 30th anniversary of the book is reviewed along with Sidman's comments on updates that he would have made if he were to revise or supplement the book. Included are some later remarks by Sidman regarding specific issues in Tactics. Continuous rates of citations are displayed and show the sustained relevance of the book, and selected themes from the book are discussed. Finally, experiences from using Tactics in lab courses and in graduate-level courses on scientific method are recapitulated, including questions raised by students, and Sidman's answers to those questions. Tactics is a true classic in behavior analysis.

A Critical Review of the Support for Variability as an Operant Dimension.

There is abundant evidence that behavioral variability is more predominant when reinforcement is contingent on it than when it is not, and the interpretation of direct reinforcement of variability suggested by Page and Neuringer, Journal of Experimental Psychology: Animal Behavior Processes, 11(3), 429-452 (1985) has been widely accepted. Even so, trying to identify the underlying mechanisms in the emergence of stochastic-like variability in a variability contingency is intricate. There are several challenges to characterizing variability as directly reinforced, most notably because reinforcement traditionally has been found to produce repetitive responding, but also because directly reinforced variability does not always relate to independent variables the same way as more commonly studied repetitive responding does. The challenging findings in variability experiments are discussed, along with alternative hypotheses on how variability contingencies may engender the high variability that they undeniably do. We suggest that the typical increase in behavioral variability that is often demonstrated when reinforcement is contingent on it may be better explained in terms of a dynamic interaction of reinforcement and extinction working on several specific responses rather than as directly reinforced.

The Emergence of Bidirectional Naming Through Sequential Operant Instruction Following the Establishment of Conditioned Social Reinforcers.

Bidirectional naming (BiN) is the integration of speaker and listener responses, reinforced by social consequences. Unfortunately, these consequences often do not function as reinforcers for behavior in children with autism. Accordingly, the repertoire of BiN is also often limited in these children. Previous research has suggested that so-called multiple-exemplar instruction, a rotation between different speaker and listener operants, may be necessary to establish BiN. The present experiment aimed to investigate whether sequential operant instruction might also work as a successful intervention to improve BiN skills after the establishment of standard social reinforcers. Standard social reinforcers were identified and established through an operant-discrimination training procedure in 4 participating children with an autism spectrum diagnosis. In the present experiment, all participants showed increased BiN after sequential operant instruction with conditioned social reinforcers contingent on relevant operants. Two of 4 participants acquired BiN skills. Moreover, the remaining 2 participants scored within the mastery criterion on listener responses, and 1 of them also met the criterion on the tact probes. Essential characteristics of an intervention, as well as the role of the echoic in the emission of BiN, are discussed.

Murray Sidman: A life of giving.

Murray Sidman's contributions to the science of behavior span many areas including avoidance behavior, coercion and its effects, stimulus control, errorless learning, programmed learning, stimulus equivalence, and single-subject methodology. He was also a great mentor to many and helped shape the discipline we now call behavior analysis. In this memoriam, we briefly highlight his scholarly legacy and share some personal anecdotes.