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Sight‐word instruction can be a useful supplement to phonics‐based methods under some circumstances. Nonetheless, few studies have evaluated the conditions under which pictures may be used successfully to teach sight‐word reading. In this study, we extended prior research by examining two potential strategies for reducing the effects of overshadowing when using picture prompts. Five children with developmental disabilities and two typically developing children participated. In the first experiment, the therapist embedded sight words within pictures but gradually faded in the pictures as needed using a least‐to‐most prompting hierarchy. In the second experiment, the therapist embedded text‐to‐picture matching within the sight‐word reading sessions. Results suggested that these strategies reduced the interference typically observed with picture prompts and enhanced performance during teaching sessions for the majority of participants. Text‐to‐picture matching also accelerated mastery of the sight words relative to a condition under which the therapist presented text without pictures.

Laboratory research has shown that when subjects are given a choice between fixed‐ratio and bi‐valued mixed‐ratio schedules of reinforcement, preference typically emerges for the mixed‐ratio schedule even with a larger ratio requirement. The current study sought to replicate and extend these findings to children's math problem completion. Using an ABCBC reversal design, four fourth‐grade students were given the choice of completing addition problems reinforced on either a fixed‐ratio 5 schedule or one of three mixed‐ratio schedules; an equivalent mixed‐ratio (1, 9) schedule, a mixed‐ratio (1, 11) schedule with a 20% larger ratio requirement, and an equally lean mixed‐ratio (5, 7) schedule without the small fixed‐ratio 1 component. This was followed by a reversal back to the preceding phase in which preference for the mixed‐ratio schedule had been observed, and a final reversal back to the mixed‐ratio (5, 7) phase. Findings were consistent with previous research in that all children preferred the mixed‐ratio (1, 9) schedule over the equivalent fixed‐ratio 5 schedule. Preference persisted for the leaner mixed‐ratio (1, 11) schedule for three of the four children. Indifference or preference for the fixed‐ratio 5 alternative was observed in phases containing the mixed‐ratio (5, 7) schedule. These results extend previous research on risky choice to children's math problem completion and highlight the importance of a small ratio component in the emergence of preference for bi‐valued mixed‐ratio schedules. Implications of these results for arranging reinforcement to increase children's academic responding are discussed.

Although choice between two alternatives has been widely researched, fewer studies have examined choice across multiple (more than two) alternatives. Past models of choice behavior predict that the number of alternatives should not affect relative response allocation, but more recent research has found violations of this principle. Five pigeons were presented with three concurrently scheduled alternatives. Relative reinforcement rates across these alternatives were assigned 9:3:1. In some conditions three keys were available; in others, only two keys were available. The number of available alternatives did not affect relative response rates for pairs of alternatives; there were no significant differences in behavior between the two and three key conditions. For two birds in the three‐alternative conditions and three birds in the two‐alternative conditions, preference was more extreme for the pair of alternatives with the lower overall pairwise reinforcer rate (3:1) than the pair with higher overall reinforcer rate (9:3). However, when responding during the changeover was removed three birds showed the opposite pattern in the three‐alternative conditions; preference was more extreme for the pair of alternatives with the higher overall reinforcer rate. These findings differ from past research and do not support established theories of choice behavior.

Choice behavior among two alternatives has been widely researched, but fewer studies have examined the effect of multiple (more than two) alternatives on choice. Two experiments investigated whether changing the overall reinforcer rate affected preference among three and four concurrently scheduled alternatives. Experiment 1 trained six pigeons on concurrent schedules with three alternatives available simultaneously. These alternatives arranged reinforcers in a ratio of 9:3:1 with the configuration counterbalanced across pigeons. The overall rate of reinforcement was varied across conditions. Preference between the pair of keys arranging the 9:3 reinforcer ratio was less extreme than the pair arranging the 3:1 reinforcer ratio regardless of overall reinforcer rate. This difference was attributable to the richer alternative receiving fewer responses per reinforcer than the other alternatives. Experiment 2 trained pigeons on concurrent schedules with four alternatives available simultaneously. These alternatives arranged reinforcers in a ratio of 8:4:2:1, and the overall reinforcer rate was varied. Next, two of the alternatives were put into extinction and the random interval duration was changed from 60 s to 5 s. The ratio of absolute response rates was independent of interval length across all conditions. In both experiments, an analysis of sequences of visits following each reinforcer showed that the pigeons typically made their first response to the richer alternative irrespective of which alternative was just reinforced. Performance on these three‐ and four‐alternative concurrent schedules is not easily extrapolated from corresponding research using two‐alternative concurrent schedules.

Chronic tic disorders ( CTDs ) involve motor and/or vocal tics that often cause substantial distress and impairment. Differential reinforcement of other behavior ( DRO ) schedules of reinforcement produce robust, but incomplete, reductions in tic frequency in youth with CTDs ; however, a more robust reduction may be needed to affect durable clinical change. Standard, fixed‐amount DRO schedules have not commonly yielded such reductions, so we evaluated a novel, progressive‐amount DRO schedule, based on its ability to facilitate sustained abstinence from functionally similar behaviors. Five youth with CTDs were exposed to periods of baseline, fixed‐amount DRO ( DRO ‐F), and progressive‐amount DRO ( DRO ‐P). Both DRO schedules produced decreases in tic rate and increases in intertic interval duration, but no systematic differences were seen between the two schedules on any dimension of tic occurrence. The DRO ‐F schedule was generally preferred to the DRO ‐P schedule. Possible procedural improvements and other future directions are discussed.

We propose quantitative experimental approaches to the question of whether positive and negative reinforcement are functionally different, and discuss scientific and ethical concerns that would arise if these approaches were pursued.

We compared outcomes of arousal and preference assessments for five adult male alleged sexual offenders with intellectual disabilities. Arousal assessments involved the use of the penile plethysmograph to measure changes in penile circumference to both deviant (males and females under the age of 18) and nondeviant (males and females over the age of 18) video clips. Paired‐stimulus preference assessments were arranged to present still images from the video clips used in the arousal assessments. Results showed correspondence between the assessments for four out of the five participants. Implications are discussed for the use of preference assessment methodology as a less intrusive assessment approach for sexual offender assessments.

Most studies of operant choice have focused on presenting subjects with a fixed pair of schedules across many experimental sessions. Using these methods, studies of concurrent variable‐ interval variable‐ratio schedules helped to evaluate theories of choice. More recently, a growing literature has focused on dynamic choice behavior. Those dynamic choice studies have analyzed behavior on a number of different time scales using concurrent variable‐interval schedules. Following the dynamic choice approach, the present experiment examined performance on concurrent variable‐interval variable‐ratio schedules in a rapidly changing environment. Our objectives were to compare performance on concurrent variable‐interval variable‐ratio schedules with extant data on concurrent variable‐interval variable‐interval schedules using a dynamic choice procedure and to extend earlier work on concurrent variable‐interval variable‐ratio schedules. We analyzed performances at different time scales, finding strong similarities between concurrent variable‐interval variable‐interval and concurrent variable‐interval variable‐ ratio performance within dynamic choice procedures. Time‐based measures revealed almost identical performance in the two procedures compared with response‐based measures, supporting the view that choice is best understood as time allocation. Performance at the smaller time scale of visits accorded with the tendency seen in earlier research toward developing a pattern of strong preference for and long visits to the richer alternative paired with brief “samples” at the leaner alternative (“fix and sample”).

This paper introduces the relational triangulation framework as a functional contextual expansion of the established Relational Frame Theory (Hayes, Barnes‐Holmes, & Roche, 2001) account of perspective‐taking. Initial support for the new framework is provided through data collected with a novel relational triangulation perspective‐taking protocol configured in the present study to show contextual influence over deriving true belief in others following the direct training of a “seeing leads to knowing” repertoire (Leslie & Frith, 1988). Eight verbally competent adults were directly trained to make operant discriminations on a first set of target stimuli (i.e., the identities of three distinct figurines) and then directly trained to make contextually controlled deictic pointing responses to a second set of target stimuli (i.e., to the relative location of a target beacon according to the signaled spatial perspective of the self vs. two others). The test for derivation was whether the stimuli that had directly acquired contextual control over deictic perspective‐taking during training would spontaneously exert contextual control over figurine discrimination relative to the spatial perspective of the two others. That is, passing the test for derivation required participants to infer that the others would “report what they were seeing” the same way that the self would if the self were in their position, suggesting coordination of the self and others. Seven of the eight participants exhibited the intended derivation of the others' “true beliefs,” confirming successful relational triangulation perspective‐taking protocol configuration for this purpose.