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Abstract Augmenting competing stimulus assessments by embedding tactics to increase stimulus engagement and disrupt challenging behavior can improve outcomes of treatments for automatically maintained self‐injurious behavior, even for treatment‐resistant subtypes. This study replicated and extended research on augmented competing stimulus assessments by reporting outcomes for 16 consecutively encountered cases with automatically maintained self‐injurious behavior (19 total applications); six participants had treatment‐responsive Subtype 1 and 10 had treatment‐resistant Subtypes 2 or 3. Fewer high‐competition stimuli were identified for individuals with treatment‐resistant subtypes. When response‐promotion and disruption tactics were applied and withdrawn, outcomes improved for six of eight applications. At least one high‐competition stimulus was still effective when maintenance probes were conducted for a subset of participants. Ultimately, at least one high‐competition stimulus was identified for each participant. Although augmenting tactics may not be necessary for all individuals, these findings provide additional support for their efficacy with treatment‐resistant self‐injurious behavior.

Abstract Research on preference and reinforcer assessments has historically focused on the evaluation of edible and leisure reinforcers, but the identification and use of individualized social reinforcers may be beneficial for several reasons. Recently, many studies have evaluated methods of assessing preference for social stimuli. The procedures and outcomes across these studies have varied greatly, and the current state of evidence for methods of assessing preference for social stimuli remains unclear. Thus, we conducted a review to synthesize all previous research in this area, evaluate the evidence for the utility of this general methodology, and identify factors that may influence its utility. Our results suggest that social preference assessments are likely to produce results that correspond with reinforcer assessment hierarchies. Preference assessment modality was one factor that influenced utility; video‐based preference assessments had greater correspondence with reinforcer assessments than did other modalities. Directions for future research and implications for the use of social preference assessments in research and practices are discussed.

Clinicians report that they often rely on descriptive assessments when developing behavior‐reduction plans despite literature suggesting that functional analysis is the most rigorous assessment method. Further, research comparing the outcomes of descriptive assessments and functional analyses is mixed, with some studies showing low correspondence and others showing high correspondence. Such persistent use of descriptive assessments suggests that they may yield useful information despite inconsistent correspondence with functional analyses. A more fine‐grained analysis of the relation between descriptive assessments and functional analyses may elucidate variables affecting their utility. We conducted a review of 48 studies that included descriptive assessments and functional analyses and evaluated several measures of correspondence between each pair of assessments. Results indicated that descriptive assessments had exact correspondence with functional analyses in 50% of comparisons. Results also suggested that descriptive assessments were more likely to accurately identify and predict the absence of a function relative to the presence of a function and that structured descriptive assessments were more likely to accurately predict functions.

A test of the evolutionary theory was conducted by replicating Bradshaw et al.'s (1977, 1978, 1979) experiments in which human participants worked on single‐alternative variable‐interval (VI) schedules of reinforcement under three punishment conditions: no punishment, superimposed VI punishment, and superimposed variable‐ratio (VR) punishment. Artificial organisms (AOs) animated by the theory worked in the same environments. Four principal findings were reported for the human participants: (1) their behavior was well described by an hyperbola in all conditions, (2) the asymptote of the hyperbola under VI punishment was equal to the asymptote in the absence of punishment, but the asymptote under VR punishment was lower than the asymptote in the absence of punishment, (3) the parameter in the denominator of the hyperbola was larger under both VI and VR punishment than in the absence of punishment, and (4) response suppression under punishment was greater at lower than at higher reinforcement frequencies. These four outcomes were also observed in the behavior of the AOs working in the same environments, thereby confirming the theory's first‐order predictions about the effects of punishment on single‐alternative responding.

Abstract Intraverbal behavior is a type of verbal behavior in which the response form has no point‐to‐point correspondence with its verbal stimulus. However, the form and occurrence of most intraverbals is under the control of multiple variables. Establishing this form of multiple control may depend on a variety of preestablished skills. The purpose of Experiment 1 was to evaluate these potential prerequisites with adult participants using a multiple probe design. The results suggest that training was not required for each putative prerequisite. In Experiment 2, probes for all skills were conducted following convergent intraverbal probes. The results showed that convergent intraverbals only emerged when proficiency of each skill was demonstrated. Finally, Experiment 3 evaluated alternating training of multiple tact and intraverbal categorization. The results showed that this procedure was effective for half of the participants.

Delay discounting reflects the rate at which a reward loses its subjective value as a function of delay to that reward. Many models have been proposed to measure delay discounting, and many comparisons have been made among these models. We highlight the two‐parameter delay discounting model popularized by Howard Rachlin by demonstrating two key practical features of the Rachlin model. The first feature is flexibility; the Rachlin model fits empirical discounting data closely. Second, when compared with other available two‐parameter discounting models, the Rachlin model has the advantage that unique best estimates for parameters are easy to obtain across a wide variety of potential discounting patterns. We focus this work on this second feature in the context of maximum likelihood, showing the relative ease with which the Rachlin model can be utilized compared with the extreme care that must be used with other models for discounting data, focusing on two illustrative cases that pass checks for data validity. Both of these features are demonstrated via a reanalysis of discounting data the authors have previously used for model selection purposes.

Abstract The purpose of the current study was to conduct a systematic replication of Fiske et al. (2015) to extend the behavior‐analytic literature on token reinforcement. Specifically, the researchers addressed several of the limitations of Fiske et al. by including specific conditioning procedures, creating a controlled history of reinforcement with the token system, including participants with and without disabilities to extend the generality of the findings, and equating the magnitude of reinforcement across the primary and paired‐token conditions. The current study evaluated the reinforcing value of tokens by using progressive‐ratio schedules to compare the efficacy of primary reinforcement, paired tokens, and unpaired tokens. The results suggest that paired tokens may function as reinforcers, but they were not as consistently effective as primary reinforcers.

Abstract Shahan et al. (2006) found that the relative rate of pigeons' pecking on two observing responses (i.e., responses that only produced an S+ or stimulus correlated with primary reinforcement) was well described by the relative rate of S+ delivery. Researchers have not evaluated the effects of S+ delivery rate in a concurrent observing response procedure with human subjects, so the necessary procedural modifications for studying the effects of conditioned reinforcement on human choice remain unclear. The purpose of the current study was to conduct an additive component analysis of modifications to the procedures of Shahan et al. (2006). We evaluated the additive effects of introducing response cost, a changeover response, and ordinal discriminative stimuli on correspondence with the results of Shahan et al. and the quality of fits of the generalized matching equation. When our procedures were most similar to those of Shahan et al., we observed low rates of observing and indifference between the two observing responses. For the group of subjects with whom all three additive components were included, we obtained the highest level of sensitivity to relative rate of S+ delivery, but the slope and R 2 of our fits of the generalized matching equation were still much lower than those obtained by Shahan et al. Potential reasons for these discrepancies, methods of resolving them, and implications for future research are discussed.

Abstract Self‐feeding with utensils represents an important step in a child's progression toward age‐typical eating and emerges in the absence of intervention for most children. In contrast, children with feeding disorders may lack the skill or motivation to self‐feed, which impedes progress toward age‐typical eating. In the current study, experimenters used a multielement design to evaluate negative reinforcement in the form of meal termination to transition six participants with a feeding disorder from caregiver‐fed to self‐fed bites and drinks. Caregivers conducted meals in which they fed the participant or prompted them to self‐feed. During self‐fed meal‐termination sessions, participants had the opportunity to end the meal contingent on self‐feeding the presented bite(s) or drink(s). Self‐feeding increased during meal‐termination sessions for all participants. The experimenters discuss these results relative to their potential to inform interventions for children with feeding disorders that progress the child toward age‐typical eating.

Abstract Previous research has commonly evaluated preference stability over time and across multiple preference assessment administrations. No studies have evaluated shifts in preference across consecutive rounds of a single preference assessment, where rounds refer to each time the experimenter resets the stimulus‐presentation array. The purpose of the present study was to examine the stability of stimulus selections across successive rounds of a multiple‐stimulus‐without‐replacement (MSWO) preference assessment with different classes of stimuli for children with autism. The study involved a secondary data analysis and calculation of preference stability across consecutive rounds using Spearman rank‐order correlation coefficients (Spearman's ) for 17 participants across 40 MSWO preference assessments. Patterns of preference stability were observed in 24 out of the 40 assessments (60%) indicating that children's preferences in this study were slightly more likely to be classified as stable than other observed patterns of responding.