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Abstract Sidman's (2000) theory of stimulus equivalence states that all positive elements in a reinforcement contingency enter an equivalence class. The theory also states that if an element from an equivalence class conflicts with a reinforcement contingency, the conflicting element will “drop out” of the class. Minster et al. (2006) found evidence that a conflicting reinforcer does not drop out of an equivalence class. To explain their results, they proposed that the reinforcer enters the class via pairing after conditional relations have been established, and when there is a conflict between the class and the contingencies, conditionally related elements that have a longer history in the class and that were brought in via reinforcement will exert stronger control. In the current study, stimulus‐reinforcer relations were established before conditional relations to assess the role of developmental order of stimulus relations on conditional‐discrimination performance. The results replicate the findings of Minster et al. (2006) but suggest that developmental order may not be an important factor contributing to maintained accuracy on baseline conditional relations. An interpretation of “dropping out” in terms of differentiated subclasses is discussed. The relevance of the results to the phenomenon known as the differential outcomes effect is also discussed.

Abstract Although owners can act as stress buffers for their dogs, whether dogs with poor early life histories with humans will respond similarly is unknown. We tested 45 dogs, 23 of which were rescued from adverse conditions, in a social paradigm in which a threatening stranger confronted them with either their owner or an unfamiliar human present. Salivary cortisol levels were assessed at three points, and the dogs' behavior and owners' responses to questionnaires were evaluated. Dogs from adverse backgrounds engaged in greater contact and exhibited more relaxed behaviors and social referencing when their owners were present. Dogs from the comparison group explored more when accompanied by their owners. Dogs from adverse backgrounds experienced greater decreases in cortisol levels from the first to third samples relative to dogs in the comparison group. Dogs from adverse backgrounds were also more likely to respond fearfully to a threatening stranger. Their owners rated them as having higher levels of stranger‐directed fear, nonsocial fear, separation‐related problems, attention seeking, and lower levels of chasing and trainability. These findings from this study suggest that early adverse environments may have lasting effects on dogs' social behavior.

Abstract Three experiments examined the effect of signaling reinforcement on rats' lever pressing on contingencies that reinforced variable responding to extend the exploration of signaled reinforcement to a schedule that has previously not been examined in this respect. In Experiment 1, rats responding on a lag‐8 variability schedule with signaled reinforcement displayed greater levels of variability ( U values) than rats on the same schedule lacking a reinforcement signal. In Experiment 2, rats responding on a differential reinforcement of least frequent responses schedule also displayed greater operant variability with a signal for reinforcement compared with rats without a reinforcement signal. In Experiment 3, a reinforcement signal decreased the variability of a response sequence when there was no variability requirement. These results offer empirical corroboration that operant variability responds to manipulations in the same manner as do other forms of operant response and that a reinforcement signal facilitates the emission of the required operant.

Disruptive behavior during instruction is a common problem in elementary classrooms. One intervention to reduce disruptive behavior is the Good Behavior Game (GBG). In this study, the students of 2 early elementary classrooms experienced 3 versions of the GBG: experimenter‐implemented, teacher‐implemented, and student‐implemented. The effects of the GBG on disruptive behavior and peer interactions were evaluated using a combined reversal and multielement design. Student preference for conditions was assessed via a group arrangement of a concurrent‐chains preference assessment. All versions of the game reduced disruptive behavior compared to baseline, but the rate of disruptive behavior was slightly higher during the teacher‐implemented sessions in Class 1. Few peer interactions occurred during the game; however, negative interactions increased slightly in both classes during the GBG. Students overwhelmingly preferred the student‐implemented version of the game. This study provides support for student implementation of the GBG and offers an approach to student shared governance in the classroom.

Abstract Steep delay and shallow probability discounting are associated with myriad problem behaviors; thus, it is important to understand factors that influence the degree of discounting. The present study evaluated the effects of economic context and reward amount on delay and probability discounting. Two hundred thirteen undergraduate psychology students completed four delay‐ or probability‐discounting tasks. Participants were exposed to hypothetical narratives involving four bank amounts ($750, $12,000, $125,000, and $2,000,000). The delayed/probabilistic amount was $3,000 for the two smaller bank amounts and $500,000 for the two larger bank amounts. The discounting tasks included five delays to, or probabilities of, receipt of the larger amount. The area under the empirical discounting function was calculated for each participant. Participants discounted delayed and uncertain outcomes more when the bank amount was smaller than the outcome (i.e., the economic context was low). Participants discounted the delayed larger amounts less than delayed smaller amounts, even when the relative economic context was the same. In contrast, probability discounting did not differ across magnitudes, which suggests that economic context may attenuate the magnitude effect in probability discounting. The results further highlight the importance of considering the economic context in delay and probability discounting.

Abstract The purpose of the current study was to compare the effects of omission and commission errors of reinforcement during tact instruction via telehealth with three children, 6 to 7 years of age, who were diagnosed with an autism spectrum disorder. We used an adapted alternating treatment design to evaluate skill acquisition of target stimuli across high‐integrity, commission errors, and omission errors conditions. The high‐integrity condition produced mastery criteria in fewer sessions compared with the integrity‐error conditions in four of six comparisons, and the omission condition reached mastery criteria in fewer sessions than the commission condition in five of six comparisons.

Due to the prevalence of words that cannot be read phonetically in the English language, sight word instruction is required to supplement phonics instruction. In this study, we manipulated stimulus disparity in sight word sets by comparing the effects of sets of sight words with the same initial letter (3 words per set, 3 total sets) versus distributing words with the same initial letter across sets when assessing acquisition of the combined set (9 words) for 5 children who ranged from 4–6 years of age using a combined adapted alternating treatments design and pre‐posttest design. All participants mastered the 3‐word sets in both teaching conditions but did not master the control sets. In general, participants required more teaching sessions when the words in sets began with the same letter. These findings are consistent with stimulus disparity research demonstrating that discrimination training is generally less efficient when comparison stimuli are similar.

Abstract Competing stimulus assessments (CSAs) are designed to identify stimuli that reduce challenging behavior through competition with its maintaining reinforcers. Recently, Haddock and Hagopian (2020) found that over 92% of CSAs described in published studies identified at least one high‐competition stimulus (i.e., a stimulus correlated with at least an 80% reduction in challenging behavior). The current study describes the outcomes of CSAs in a retrospective consecutive controlled case series study of 35 cases (individuals) admitted to an inpatient setting. Findings on the limited relation between the level of stimulus engagement and reductions in challenging behavior were replicated; however, the efficacy of CSAs was lower (only 47% of CSAs were successful in identifying one or more high‐competition stimuli). Discrepant findings across studies on the efficacy of CSAs are discussed in terms of differences in the sample participants and how outcomes are reported, which vary depending on the study's research questions.

Abstract We hypothesized that a three‐sample conditional discrimination can emerge as a result of learning conditional discriminations with relational stimuli. After learning three first‐order conditional discriminations AB, PQ, and CD, we taught a second‐order conditional discrimination XAB in which X1 indicated selection of related stimuli (e.g., A1 and B1) and X2 of unrelated stimuli (e.g., A1 and B2). Then, we probed the emergence of conditional discriminations PQX and XCD in which the X stimuli were comparisons and contextual stimuli, respectively. Finally, a conditional discrimination was probed with stimuli P, Q, and C as samples and D1 and D2 as comparisons. When the P and Q stimuli were related (and related to X1 in PQX), all participants selected the D stimulus that was related to the C stimulus (D1 when C1 was present and D2 when C2 was present); when the P and Q stimuli were unrelated (and related to X2 in PQX), they selected the D stimulus unrelated to the C stimulus (D2 when C1 and D1 when C2), which demonstrated emergence based on the relations established among all stimuli. In Experiment 2, the teaching of XAB was omitted and only one in six participants demonstrated emergence, which indicated that relational stimuli X1 and X2 played an important role in emergence. Thus, a new type of emergence that mimics analogical reasoning was demonstrated. The obtained outcome suggests that this procedure provides a learning foundation for acquiring reasoning capabilities.

Physical inactivity has increasingly affected public health in the United States during the COVID‐19 pandemic as it is associated with chronic diseases such as arthritis, cancer, and heart disease. Contingency management has been shown to increase physical activity. Therefore, the present study sought to evaluate the effects of an escalating schedule of monetary reinforcement with a reset contingency on physical activity, as compared between 2 counterbalanced groups in which a monetary deposit of $25 was either required (deposit group) or not (no‐deposit group). Twenty‐five adults wore Fitbit accelerometers to monitor step counts. An ABA reversal design was used; in the 2 baseline phases, no programmed contingencies were in place for step counts. During intervention, step goals were set using a modified 70 th percentile schedule with a 7‐day window: Reaching the first goal would result in $0.25, and incentives increased by $0.25 for each subsequent day in which the goal was met. Failure to reach a goal resulted in a reset of the monetary incentive value to $0.25. Ten out of 12 participants from the deposit group were determined to be responders to intervention, whereas 8 out of 13 participants from the no‐deposit group were determined to be responders to intervention. Overall, there were no significant differences between the groups' step counts. However, the deposit group's intervention was cheaper to implement, which suggests that deposit contracts are a viable modification for physical activity interventions.