Concurrent schedules: a quantitative relation between changeover behavior and its consequences

Data from several published experiments on concurrent variable-interval schedules were analyzed with respect to the effects of changeover delay on the time spent responding on a schedule before changing to an alternate schedule: i.e., the interchangeover time. Interchangeover time increases as the duration of the changeover delay increases, and the present analysis shows that a power function describes the relation. The power relation applied in spite of numerous differences in the experiments: different variable-interval schedules for the concurrent pairs; equal or unequal reinforcement rates for the schedules of the concurrent pairs; different durations of the changeover delay; response-dependent or response-independent reinforcers; pigeons or rats as subjects; different reinforcers. A power function also described the data in experiments where the changeover incurred a timeout, where a fixed ratio was required to changeover, and also when asymmetrical changeover delays were used.     

Effects of fixed-ratio sample and choice response requirements upon oddity matching

Three pigeons were trained on oddity matching in which either 1, 4, 8, 16, or 32 sample-key observing responses were required to turn off the sample stimuli and turn on the comparison stimuli. Oddity accuracy increased when the observing-response requirement was raised and decreased when the requirement was lowered. Next, while the observing requirement was maintained at one response, the number of responses required to the comparison stimuli was either 1, 4, 8, 16, or 32. Under these conditions, choice was defined as the comparison that first accumulated the required number of responses. In general, increasing the comparison-response requirement decreased accuracy and lowering the comparison requirement increased accuracy. The fixed-ratio observing requirements appeared to facilitate control by stimuli serving an instructional function.     

Demand for food on fixed-ratio schedules as a function of the quality of concurrently available reinforcement

Six rats lever pressed for food on concurrent fixed-ratio schedules, in a two-compartment chamber. In one compartment, mixed diet pellets were delivered on fixed-ratio schedules of 1, 6, 11, and 16; in the other, either no food was delivered, or sucrose or mixed diet pellets were delivered on fixed-ratio 8. The number of pellets obtained in the first compartment declined as a function of fixed-ratio size in that compartment in all three conditions, but the decline was greatest overall with mixed diet pellets concurrently available in the other compartment, and least with no food concurrently available. The result is discussed in terms of economic demand theory, and is consistent with the prediction that elasticity of demand for a commodity (defined in operant terms as the ratio of the proportionate change in number of reinforcements per session to the proportionate change in fixed-ratio size) is greater the more substitutable for that commodity are any concurrently available commodities.     

Producing a change from competition to sharing: effects of large and adjusting response requirements

Pairs of high-school students matched-to-sample for money. On each trial, the first pair member to complete a fixed ratio of knob-pulling responses could work the matching problem on that trial. Competition occurred when both pair members responded for the problem. Sharing occurred when only one pair member responded on each trial, and the subjects alternated trials. Hence, sharing requires less responding and still allows a moderate number of reinforcers for each subject. Recent research has shown that increasing the response requirement to the point that it may have aversive properties will produce a change from competition to sharing. A related variable is an adjusting schedule that adjusts the subjects' response requirements so that their abilities to take reinforcers are equal. In this way, subjects might learn that competition requires more responding but produces no more reinforcers. However, recent research also suggests that competition decreases over sessions without experimental manipulations. Because of this possibility of a time-related variable, ratio size and an adjusting schedule were studied in a group design. Competition did decrease for all groups over sessions, but the large-ratio groups switched from competition to sharing sooner than the low-ratio groups. The adjusting schedule had a similar but smaller effect.     

Food deliveries during the pause on fixed-interval schedules

Pigeons were trained on fixed-interval schedules of food delivery. In Experiments I and II, the fixed interval was initiated by the previous fixed-interval reinforcer; in Experiment III, the fixed interval was initiated by the first key peck following the preceding fixed-interval reinforcer (a chain fixed-ratio one, fixed-interval schedule). During the postreinforcement pause, variable-time schedules delivered food independent of any specific response. Rate of food delivery during the pause had only small effects on pause duration in Experiments I and II. In Experiment III, however, pause duration increased systematically with the rate of food delivery during the pause. These data suggest that the momentary proximity to reinforcement delivered via the fixed-interval schedule exerts potent control over pause termination. Additional analysis revealed that pause termination was unaffected by the intermittent delivery of food during the pause. Such data suggest that the temporal control by fixed-interval schedules is highly resistant to interference.     

Relation between level of food deprivation and rate of schedule-induced attack

The relation between food deprivation and schedule-induced attack was investigated in four White Carneaux pigeons. Attack toward a mirror target was induced by a schedule of reinforcement in which 3-sec food presentations occurred at alternate intervals of 15 and 120 sec (multiple fixed-time 15-sec fixed-time 120-sec schedule). A continuous tone was presented during the 15-sec periods; it was absent during the 120-sec periods. Each pigeon was tested at 65, 80, and 95% of its free-feeding weight in ascending, descending, and ascending orders, respectively. Two relations were apparent; an inverse relation between body weight and rate of attack, and a tendency for rate of attack to increase during the experiment. Reduction or elimination of attack when the mirror was covered with brown paper for some sessions indicated that the results were due neither to changes in activity that might covary with weight nor to habituation to the experimental situation.     

Alternative response training, differential reinforcement of other behavior, and extinction in squirrel monkeys (Saimiri sciureus)

In Experiment I, (a) extinction, (b) extinction plus reinforcement of a discrete alternative response, and (c) differential reinforcement of other behavior were each correlated with a different stimulus in a three-component multiple schedule. The alternative-response procedure more rapidly and completely suppressed behavior than did differential reinforcement of other behavior. Differential reinforcement of other behavior was slightly more effective than extinction alone. In Experiment II, reinforcement of specific alternative behavior during extinction and differential reinforcement of other behavior were used in two components, while one component continued to provide reinforcement for the original response. Once again, the alternative-response procedure was most effective in reducing responding as long as it remained in effect. However, the responding partially recovered when reinforcement for competing behavior was discontinued. In general, responding was less readily reduced by differential reinforcement of other behavior than by the specific alternative-response procedure.     

Response to name in children with autism: Treatment,generalization, and maintenance

Deficits in response to name (RTN) are an early indicator of autism spectrum disorder (ASD), and RTN is a treatment goal in many early intervention curricula for children with ASD. However, little research has empirically evaluated methods for increasing RTN in children with ASD. We evaluated a series of conditions designed to increase RTN for 4 children with ASD using a multielement experimental design. The schedules of tangible reinforcement were thinned after mastery and generalization was tested across people and contexts. Tangible reinforcers were necessary to increase RTN for all 4 participants, and the schedule of reinforcement was successfully thinned with all participants after intervention. Generalization was also observed across people and experimental contexts.     

Experimental evaluation of matching via a commercially available basketball video game

Many recent nonlaboratory-based quantitative analyses of behavior have relied on archival competitive sporting data. However, the ratio-based reinforcement schedules in most athletic competitions and the correlational nature of archival data analyses raise concern over the contributions of such findings to the behavior analytic literature. The current experiment evaluated whether matching in a human operant paradigm would approximate matching observed in nonlaboratory-based sports data. To this end, we used in-game attributes to parametrically manipulate 2- and 3-point shooting in a commercially available basketball video game. The behavior of 6 of 9 participants conformed to the generalized matching equation. These results suggest matching in sporting contexts may be a product of restricted nonindependent concurrent random-ratio schedules. Implications of this experiment, including those in applied behavior analysis and potential influence on gamification, are discussed.     

Validity of the multiple-stimulus without replacement preference assessment for edible items

Studies have shown that the multiple-stimulus without replacement (MSWO) preference assessment is an effective assessment format for identifying preferred items. However, it is possible that factors other than reinforcer quality might influence selections by some individuals when the MSWO array consists of edible items. The validity of the MSWO results was evaluated by comparing items identified as most and least preferred by the MSWO assessment in a concurrent-schedule (CS) format. Varying edible items were used in each study. The MSWO format accurately identified the higher quality edible item for most participants across studies (76%); however, the MSWO format did not predict the highest quality edible item in the CS assessment for 20% to 30% of participants in each study.