Recent work in reinforcement learning has demonstrated a choice preference for an option that has a lower probability of reward (A) when paired with an alternative option that has a higher probability of reward (C), if A has been experienced more frequently than C (the frequency effect). This finding is critical as it is inconsistent with…

The current study examined whether bystander behaviours in class were associated with being perpetrators of ethnic victimization and whether they moderated the association between disengagement from morality and perpetrating ethnic-based victimization. The sample included 1065 adolescents residing in Sweden (M[subscript age] = 13.12, SD=.42; 55%…

The high-probability (high-p) instructional sequence typically consists of the delivery of a series of high-p instructions immediately followed by the delivery of a low-probability (low-p) instruction and is a commonly used procedure to increase compliance among children with intellectual disabilities. In the current study, we used withdrawal…

Non-compliance is a challenge for practitioners serving children with and without disabilities. Many interventions have been developed to increase compliance. High-probability request sequences (HPRS), an antecedent-based intervention that is based on behavioral momentum theory, is one way to increase compliant behavior. HPRS includes the…

The adaptive learning problem concerns how to create an individualized learning plan (also referred to as a learning policy) that chooses the most appropriate learning materials based on a learner's latent traits. In this article, we study an important yet less-addressed adaptive learning problem--one that assumes continuous latent traits.…

Limited information is available concerning the specificity of the forms and functions of aggressive behavior exhibited by boys with fragile X syndrome (FXS). To investigate these relationships, we conducted indirect functional assessments of aggressive behavior exhibited by 41 adolescent boys with FXS and 59 age and symptom-matched controls with…

Observational learning is an important mechanism for cognitive and social development. However, the neurophysiological mechanisms underlying observational learning in children are not well understood. In this study, we used a probabilistic reward-based observational learning paradigm to compare behavioral and electrophysiological markers of…

Learning to choose adaptively when faced with uncertain and variable outcomes is a central challenge for decision makers. This study examines repeated choice in dynamic probability learning tasks in which outcome probabilities changed either as a function of the choices participants made or independently of those choices. This presence/absence of…

When dealing with children who exhibit challenging behaviors there are no known interventions that work for all students or at all times. Thus, intervention for these students is often implemented in a trial and error manner. This article provides a logic for considering probability as a factor in selecting strategies. Understanding that some…

Some researchers claim that variability is an operant dimension of behavior. The present paper reviews the concept of operant behavior and emphasizes that differentiation is the behavioral process that demonstrates an operant relation. Differentiation is conceived as change in the overlap between two probability distributions: the distribution of…

Reinforcement learning approaches to cognitive modeling represent task acquisition as learning to choose the sequence of steps that accomplishes the task while maximizing a reward. However, an apparently unrecognized problem for modelers is choosing when, what, and how much to reward; that is, when (the moment: end of trial, subtask, or some other…

Barba's (2012) article deftly weaves three main themes in one argument about operant variability. From general theoretical considerations on operant behavior (Catania, 1973), Barba derives methodological guidelines about response differentiation and applies them to the study of operant variability. In the process, he uncovers unnoticed features of…

Learning about the structure of the world requires learning probabilistic relationships: rules in which cues do not predict outcomes with certainty. However, in some cases, the ability to track probabilistic relationships is a handicap, leading adults to perform non-normatively in prediction tasks. For example, in the "dilution effect,"…

The target paper by Barba (2012) raises issues that were the focus of the author's first two publications on operant variability. The author will describe the main findings in those papers and then discuss Barba's specific arguments. Barba has argued against the operant nature of variability. (Contains 2 figures.)

In a temporal double bisection task, animals learn two discriminations. In the presence of Red and Green keys, responses to Red are reinforced after 1-s samples and responses to Green are reinforced after 4-s samples; in the presence of Blue and Yellow keys, responses to Blue are reinforced after 4-s samples and responses to Yellow are reinforced…