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Abstract The Fair Labor Standards Act suggests that short rest periods of 5–20 min may improve employee productivity, but there is limited experimental research on the topic. The current study compared productivity when breaks were not required (i.e., control session) compared with when breaks were programmed by the experimenter (i.e., experimental session). Sixteen undergraduate students completed two 2‐hr sessions of a simulated check‐processing task. Half of the participants were randomly assigned to receive the experimental session (5‐min breaks every 20 min) first with the control session second, and the other half received the control first and the experimental session second. The results showed that 75% of participants completed more checks during the experimental session than during the control session and the difference was statistically significant. Most participants took more unprogrammed break time during control sessions compared with experimental sessions. Implications for future research and the value of work breaks are discussed.

In 1948, Skinner described the behavior of pigeons under response‐independent schedules as “superstitious,” and proposed that the responses were reinforced by contiguous, adventitious food deliveries. Subsequently, response‐independent schedules have been of interest to both basic and applied researchers, first to understand the mechanisms involved, and later, as “noncontingent reinforcement” (NCR) to reduce undesirable behavior. However, the potential superstitious effects produced by these schedules have been challenged, with some researchers arguing that antecedent variables play a significant role. This paper examines the evidence for adventitious reinforcement from both laboratory and applied research, the results of which suggest that antecedent, nonoperant functions may be important in fully understanding the effects of NCR. We propose an applied‐basic research synthesis, in which attention to potential nonoperant functions could provide a more complete understanding of response‐independent schedules. We conclude with a summary of the applied implications of the nonoperant functions of NCR schedules.

Abstract The generalized matching law predicts performance on concurrent schedules when variable‐interval schedules are programmed but is trivially applicable when independent ratio schedules are used. Responding usually is exclusive to the schedule with the lowest response requirement. Determining a method to program concurrent ratio schedules such that matching analyses can be usefully employed would extend the generality of matching research and lead to new avenues of research. In the present experiments, ratio schedules were programmed dependently such that responses to either of the two options progressed the requirement on both schedules. Responding is not exclusive because the probability of reinforcement increases on both schedules as responses are allocated to either schedule. In Experiment 1, performance on concurrent variable‐ratio schedules was assessed, and reinforcer ratios were varied across conditions to investigate changes in sensitivity. Additionally, the length of a changeover delay was manipulated. In Experiment 2, performance was compared under concurrently available, dependently programmed variable‐ratio and fixed‐ratio schedules. Performance was well described by the generalized matching law. Increases in the changeover delay decreased sensitivity, whereas sensitivity was higher when variable‐ratio schedules were employed, compared with fixed‐ratio schedules. Concurrent ratio schedules can be a viable approach to studying functional differences between ratio and interval schedules.

Abstract Instruction in auditory–visual conditional discriminations for young children with autism spectrum disorder is typically based on either a conditional‐only or a simple‐conditional method. In this study, we evaluated a modified simple‐conditional method in which we removed the steps for which visual comparisons were presented in isolation. We compared this modified simple‐conditional method with the conditional‐only method when teaching auditory–visual conditional discriminations to six young Chinese children with autism spectrum disorder. We included two efficiency measures: total sessions and time to mastery. Our results replicated the findings of previous research in that both methods were efficacious for all but one participant. Although efficacy outcomes were similar across methods, the conditional‐only method was more efficient across participants according to sessions and time to mastery. Thus, the results add to support for the use of the conditional‐only method to teach auditory–visual conditional discriminations.

Abstract Stimulus equivalence is a central paradigm in the analysis of symbolic behavior, language, and cognition. It describes emergent relations between stimuli that were not explicitly trained and cannot be explained by primary stimulus generalization. In recent years, researchers have developed computational models to simulate the learning of equivalence relations. These models have been used to address primary theoretical and methodological issues in this field, such as exploring the underlying mechanisms that explain emergent equivalence relations and analyzing the effects of training and testing protocols on equivalence outcomes. Nonetheless, although these models build upon general learning principles, their operation is usually obscure for nonmodelers, and in the field of stimulus equivalence computational models have been developed with a variety of approaches, architectures, and algorithms that make it difficult to understand the scope and contributions of these tools. In this paper, we present the state of the art in computational modeling of stimulus equivalence. We seek to provide concise and accessible descriptions of the models' functioning and operation, highlight their main theoretical and methodological contributions, identify the existing software available for researchers to run experiments, and suggest future directions in the emergent field of computational modeling of stimulus equivalence.

Abstract Differential reinforcement of alternative behavior (DRA) without extinction is an effective intervention for reducing problem behavior maintained by socially mediated reinforcement, particularly when implementing dense schedules of reinforcement for appropriate behavior. Thinning schedules of reinforcement for an alternative response may result in resurgence of problem behavior. Resurgence may be of particular concern in the treatment of problem behavior without extinction because problem behavior that resurges is also likely to encounter reinforcement and thus can be expected to maintain. In the present investigation, we compared the effectiveness of single and concurrent DRA schedules in decreasing the probability of resurgence when problem behavior continues to produce reinforcement throughout all phases of the evaluation. Concurrent DRA schedules reduced or eliminated the likelihood of resurgence compared with a single DRA schedule during a treatment challenge.

Tversky and Kahneman (1981) told participants to imagine they were at a store about to purchase an item. They were asked if they would be willing to drive 20 min to another store to receive a $5 discount on the item's price. Most participants were willing, but only when the original price of the item was small ($15); when the original price was relatively large ($125), most said they would not drive 20 min for a $5 discount. We examined this framing effect in 296 participants, but instead used a psychophysical‐adjustment procedure to obtain quantitative estimates of the discount required with different (a) item prices, (b) delays until the item's receipt, and (c) opportunity costs (in “driving” vs. “delivery” tasks). We systematically replicated Tversky and Kahneman's results, but also extended them by showing a substantial influence of opportunity costs on the consumer discounts required. A behavioral model of delay discounting—additive‐utility theory—accounted for 97% of the variance in these consumer discounts.

Abstract We compared the effects of different “mastery” criteria and doses on the acquisition and maintenance of sight words for 4 second graders with and without disabilities. First, we replicated Set Analysis and Operant Analysis conditions where participants were taught sight words in 20‐trial (4 operants, 5 opportunities) sessions. Acquisition criteria were applied to a set of 4 operants or to individual operants, respectively. Second, we extended the literature by evaluating a lower dose of the Operant Analysis condition in a 12‐trial session (4 operants, 3 opportunities). Thus, we compared 3 conditions—Set Analysis 5, Operant Analysis 5, and Operant Analysis 3. All participants acquired novel sight words fastest and required far fewer teaching trials to maintain each sight word under Operant Analysis 3 compared with Set Analysis 5 and Operant Analysis 5 conditions. Implications for arranging acquisition criteria and the interaction with trial‐dosages are discussed.

Previous discounting research has focused on relatively simple situations (e.g., choosing between immediate and delayed gains, or between immediate and delayed losses) and the relations among amount, delay, and subjective value in such situations are now well established. Many everyday choice situations, however, are more complex, involving alternatives that combine gains and losses. In two experiments, participants discounted a monetary outcome that combined an immediate gain with a delayed loss. Consistent with the discounting framework, the value of the combination was approximately equal to the difference between the (undiscounted) value of the immediate gain and the (discounted) value of the delayed loss. More precise predictions of the relative subjective value of the delayed loss component of a combination were given by the same hyperboloid function that describes discounting in simple choice situations where outcomes only involve gains or losses, not both. As in previous studies, when the outcome was a simple one consisting of only a delayed loss, discounting was not affected by the amount of that loss. Surprisingly, however, when the loss was preceded by a gain, the degree to which the combination was discounted was affected by the amount of the loss. Notably, discounting of the delayed loss component of the combination decreased with the amount of the loss in a fashion similar to that observed with simple delayed gains, where smaller amounts are discounted more steeply than larger amounts. Choice situations involving immediate gains followed by delayed losses pose iconic self‐control problems, and the present findings support the application of the discounting framework to these important everyday problems.

Abstract We investigated the effects of differential and nondifferential reinforcers on divided control by compound‐stimulus dimensions. Six pigeons responded in a delayed matching‐to‐sample procedure in which a blue or yellow sample stimulus flashed on/off at a fast or slow rate, and subjects reported its color or alternation frequency. The dimension to report was unsignaled (Phase 1) or signaled (Phase 2). Correct responses were reinforced with a probability of .70, and the probability of reinforcers for errors varied across conditions. Comparison choice depended on reinforcer ratios for correct and incorrect responding; as the frequency of error reinforcers according to a dimension increased, control (measured by log d ) by that dimension decreased and control by the other dimension increased. Davison and Nevin's (1999) model described data when the dimension to report was unsignaled, whereas model fits were poorer when it was signaled, perhaps due to carryover between conditions. We are the first to test this quantitative model of divided control with reinforcers for errors and when the dimension to report is signaled; hence, further research is needed to establish the model's generality. We question whether divided stimulus control is dimensional and suggest it may instead reflect joint control by compound stimuli and reinforcer ratios.