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The risk for serious injury and death to children during motor vehicle accidents can be greatly reduced through the correct use of child passenger safety restraints (CPSRs). Unfortunately, most CPSRs are installed or used incorrectly. This study examined the effectiveness of behavioral skills training (BST) to teach 10 participants to install rear‐facing CPSRs correctly using a multiple baseline design. Results show that installation errors were common for all participants during baseline. After BST, all 10 participants were able to install the rear‐facing CPSR without error. An extension probe to assess whether the skills taught during BST extended to forward‐facing installation showed that each participant made at least 1 critical error.

In studies of operant choice, when one schedule of a concurrent pair is varied while the other is held constant, the constancy of the constant schedule may exert discriminative control over performance. In our earlier experiments, schedules varied reciprocally across components within sessions, so that while food ratio varied food rate remained constant. In the present experiment, we held one variable‐interval (VI) schedule constant while varying the concurrent VI schedule within sessions. We studied five conditions, each with a different constant left VI schedule. On the right key, seven different VI schedules were presented in seven different unsignaled components. We analyzed performances at several different time scales. At the longest time scale, across conditions, behavior ratios varied with food ratios as would be expected from the generalized matching law. At shorter time scales, effects due to holding the left VI constant became more and more apparent, the shorter the time scale. In choice relations across components, preference for the left key leveled off as the right key became leaner. Interfood choice approximated strict matching for the varied right key, whereas interfood choice hardly varied at all for the constant left key. At the shortest time scale, visit patterns differed for the left and right keys. Much evidence indicated the development of a fix‐and‐sample pattern. In sum, the procedural difference made a large difference to performance, except for choice at the longest time scale and the fix‐and‐sample pattern at the shortest time scale.

The current experiment examined the degree to which locally varying food probabilities on two keys across time since food presentations can continue to control choice until the next food delivery. In two sets of conditions, the probability of food delivery being made available on one key relative to the other key varied sinusoidally across a 1‐min period following each food delivery. In Set 1, food‐probability changes were unsignaled and the number of cycles per min was varied across conditions. In Set 2, there were always two complete cycles of the sinusoid in the 1‐min period, and brief key‐color changes were arranged at a selection of fixed times since food delivery to signal portions of the sinusoid. In Set 1, control of choice by local probability of food on each key decreased over time since food delivery. Control by local food probabilities was greater in conditions that arranged fewer cycles per min. The onset of stimulus changes in Set 2 led to a transient reinstatement of local control by food probabilities regardless of the portion of the sinusoidal variation in food probabilities signaled by the stimuli. However, in conditions where the same colored stimuli signaled different portions of the sinusoidal variation in food‐delivery probabilities, stimulus changes attenuated joint control by elapsed time and food‐probability values. These results suggest that, changing relative food probabilities and stimuli can direct preference toward the likely location of the next food delivery across time since a food presentation, although the degree to which control over choice will be maintained across elapsed time depends on how experimenter‐arranged contingencies are mapped onto elapsed time.

Behavioral Momentum Theory (BMT) has inspired animal models of treatment relapse. We translated the models of reinstatement and resurgence into clinical procedures to test whether relapse tests would replicate behavior pattern found in basic research. Following multiple schedule baseline reinforcement of a 16‐year‐old male's problem behavior at equal rates by two therapists, treatment was introduced using a variable‐interval, variable‐time (VI VT) schedule arrangement with therapists delivering reinforcers at different rates. Despite the differing rates of VI VT reinforcers, the treatment produced comparable reductions in problem behavior. Following successful treatment, the two therapists discontinued treatment and resumed reinforcement of problem behavior at equal rates that constituted a reinstatement of baseline conditions. As predicted by BMT, reinstatement resulted in an immediate return of high rates of problem behavior but was 2.6 times higher for the therapist using the higher rate VI VT treatment. A second treatment phase was implemented followed by a test of resurgence in a single extended extinction session conducted separately for each therapist. The unequal VI VT treatment rates by therapists resulted in 2.1 times greater responding in the resurgence test for the therapist who implemented the higher rate VI VT procedure. These results are consistent with basic research studies and BMT.

Although massed‐trial instruction, distributed‐trial instruction, and task interspersal have been shown to be effective methods of teaching skills to children with autism spectrum disorders, they have not been directly compared. In the current study, we taught 6 children to tact shapes of countries using these methods to determine which would result in the quickest acquisition. Five of the 6 participants acquired the targets in the massed‐trial condition before the other 2 conditions.

We investigated the relative effects of simple and complex auditory‐visual discrimination training using an adapted alternating treatments design to establish derived stimulus relations in 2 children who had been diagnosed with autism and 1 typically developing peer. Emergence of untrained conditional relations was observed after training in both conditions, with a possible advantage of simple‐sample training for 1 participant. Results of generalization and follow‐up probes were mixed.

Descriptions of steady‐state patterns of choice allocation under concurrent schedules of reinforcement have long relied on the “generalized matching law” (Baum, 1974), a log‐odds power function. Although a powerful model in some contexts, a series of conflicting empirical results have cast its generality in doubt. The relevance and analytic relevance of matching models can be greatly expanded by considering them in terms of compositions (Aitchison, 1986). A composition encodes a set of ratios (e.g., 5:3:2) as a vector with a constant sum, and this constraint (called closure ) restricts the data to a nonstandard sample space. By exploiting this sample space, unbiased estimates of model parameters can be obtained to predict behavior given any number of choice alternatives. Additionally, the compositional analysis of choice provides tools that can accommodate both violations of scale invariance and unequal discriminability of stimuli signaling schedules of reinforcement. In order to demonstrate how choice data can be analyzed using the compositional approach, data from three previously published studies are reanalyzed. Additionally, new data is reported comparing matching behavior given four, six, and eight response alternatives.

Pigeons demonstrate associative symmetry after successive matching training on one arbitrary and two identity relations (e.g., Urcuioli, 2008). Here, we tested whether identity matching training is necessary for this emergent effect. In Experiment 1, one group of pigeons (Dual Oddity) learned hue–form arbitrary matching and two oddity relations which shared sample and comparison elements with the arbitrary relations. A second (Control) group learned the same hue–form matching task and a second (form–hue) arbitrary task which, together with hue oddity, shared only the samples with the hue–form relations. On subsequent symmetry probe trials, four Dual Oddity pigeons exhibited higher probe‐trial response rates on the reverse of the positive than negative hue–form baseline trials, demonstrating associative symmetry. None of the Control pigeons, on the other hand, exhibited associative symmetry. Experiment 2 showed that subsequently changing one of the two oddity baseline relations to identity matching in the Dual Oddity group yielded antisymmetry in three of five pigeons. These results are consistent with predictions derived from Urcuioli's (Urcuioli, 2008) theory of pigeons' stimulus class formation and demonstrate that identity training is not necessary for associative symmetry to emerge after arbitrary matching training in pigeons.

Log‐survivor analyses of interresponse times suggest that the behavior of rats responding under single variable‐interval schedules is organized into bouts (i.e., periods of engagement and disengagement). Attempts to generalize this analysis to the key pecking in pigeons, however, have failed to produce the characteristic broken‐stick appearance typically obtained with rats. This failure may be due to a relatively low rate of reinforcement for engaging in alternative behavior experienced by pigeons. The present study tested this hypothesis by exposing four pigeons to concurrent schedules of reinforcement for key pecking, first without a changeover delay (COD) and then with a COD. In this arrangement, one of the concurrent options was treated as the target response and the rate of reinforcement for that option was manipulated across conditions. The other option provided explicit reinforcement for engaging in an alternative response (i.e., explicit reinforcement for disengaging from the target response). In the absence of a COD, log‐survivor plots for three of the pigeons were approximately linear, thus providing no evidence that responding was organized into bouts. When a COD was present, plots were broken stick in appearance, indicating a bout structure had been generated in the pigeons' behavior. Both bout length and the rate of bout initiations were a function of differences in rate of reinforcement. These data suggest that behavior may become organized into bouts when contingencies create sufficiently long visits to both the target behavior and the extraneous behavior. Fits of a double‐exponential model deviated systematically from the actual plots due to the presence of a plateau between the two limbs. An alternative, double‐gamma, model was explored, and it provided a considerably better fit than did the double‐exponential.