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Effective nonpunitive procedures for reducing counterproductive classroom behaviors are of potential benefit to both students and teachers. A recent strategy for dealing with this class of problem behaviors involves the reinforcement of acceptably low levels of such behavior. The laboratory version of this procedure, called differential reinforcement of low rates of responding (or DRL), provides for a reinforcer to be delivered contingent upon a response that is separated from the last preceding response by a minimum amount of time. To make this procedure more amenable to classroom use, the present authors have modified it so that a reinforcer is delivered if fewer than a specified number of responses occur within a preset time interval (Deitz and Repp, Journal of Applied Behavior Analysis, 1973, 6, 457–463). Previous studies using this procedure have found it effective in reducing and maintaining low rates of targeted behaviors. However, these effects have been demonstrated with groups of subjects and/or individuals from dependent populations. The present study investigated use of this modified DRL procedure with individual students in normal elementary classrooms. In the first of three studies, “talk‐outs” of an 11‐yr‐old fifth‐grade male were reduced when nonexchangeable gold stars were made contingent on two or fewer responses per session. During baseline sessions, an average of 4.45 talkouts were observed per 45‐min session. Average responding subsequently fell to 1.83 when the modified DRL contingency was applied, increased to 7.60 during a reversal phase, and dropped again to an average of 1.20 when the contingency was reapplied. In the second study, out‐of‐seat behavior of a 12‐yr‐old sixth‐grade female was reduced when gold stars were made contingent on two or fewer responses per 45‐min class period. Baseline responding averaged 6.10 responses per session. When the contingency was applied, average responding fell to 0.16. During the reversal period, responding increased to an average of 6.00 and fell again, after the contingency was re‐introduced to an average of 0.40. In the third study, a reduction in both talking‐out and out‐of‐seat behaviors of another 11‐yr‐old fifth‐grade male was demonstrated with a multiple‐baseline design. Using different lengths of baselines, gold stars were made contingent first on a low rate of out‐of‐seat behavior, and then on a low rate of talk‐outs. Out‐of‐seat responding fell from a baseline average of 7.50 to a treatment average of 1.14. Talk‐outs went from a baseline average of 4.66 to a treatment average of 1.14. In all three studies, the modified DRL procedure proved effective with the children and was manageable by the classroom teacher. For the students, nonexchangeable conditioned reinforcers (stars) were sufficient to maintain lowered rates of inappropriate behavior with the modified DRL schedule; there was no need for an elaborate token economy, a process that in many cases may be only a form of behavioral “overkill”. As in other studies investigating DRL schedules, students were not informed of their accumulation of responses; the differential effects of providing or withholding this feedback need to be investigated. Overall, these studies add single‐subject replication with normal children to the literature on modified DRL procedures.

Rats received food following lever‐press durations between t and t + t′ sec where t was 2, 4, or 8 sec and t′ was 0.25t, 0.50t, or 1.00t sec. Modal press durations were greater than t but less than t + t′ in all cases. Distributions of press durations were lower and broader for larger values of t. Lower t′/t ratios produced lower median press durations and relatively narrower press‐duration distributions. Median press duration was a power function of t within a t′/t ratio condition, corresponding to previous results for latency, interresponse time, and response durations.

Prior studies have reported that generalization gradients are not steepened if periods of non‐reinforcement in S— follow and are not interspersed with periods of reinforcement in S+. Sharper gradients are produced by this massed‐extinction procedure if it is preceded by prior discriminative training on a dimension orthogonal to the S+, S— dimension. The present study, using pigeons, found that generalization gradients along the wavelength dimension were steepened by massed‐extinction sessions in 570 nm that had been preceded by: (1) discriminative training in which the S+ was a 550‐nm light and the S— was a black vertical line superimposed on the 550‐nm light; Final Acceptance (2) non‐differential reinforcement training with a 550‐nm light and a black vertical line superimposed on the 550‐nm light; Final Acceptance (3) reinforcement training with only the 550‐nm light. Massed‐extinction sessions were administered until the response rate in the presence of the 570‐nm stimulus was one‐tenth of the mean response rate in the presence of the 550‐nm stimulus during prior reinforcement training. Prior studies have used a time‐dependent criterion, rather than a response‐rate criterion of extinction, and this difference may be responsible for the differences in the effects of massed extinction on stimulus control.

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Behavioral self‐control procedures, composed of self‐assessment, self‐recording, self‐determination and administration of reinforcement, were introduced into a regular third‐grade classroom immediately after a baseline period. The procedures produced a small and unstable increase in the level of on‐task behavior in eight of the nine subjects. After a second baseline period, a cueing procedure was introduced, using a chart specifying on‐task behavior. This enabled within‐lesson changes in on‐task behavior to be posted clearly for the children. The cueing procedure combined with the self‐control procedures produced a high and stable increase in on‐task behavior in all subjects.

A contingency contracting program designed to increase study rate and subsequent test performance was implemented with a group of undergraduate psychology students. The function of the contingency contracting program in producing increased study rate was evaluated by individual experiments with each student in an experimental contracting group. The overall effect of the program on test performance was assessed by comparing the final scores for the course earned by the experimental group with those earned by two matched control groups. A reversal procedure established that contingency contracting did significantly increase the study rate of students of a wide range of ability. However, it was selectively effective in improving the test performance of below‐average students only. Study rate gains in contracted courses did not generalize to noncontracted courses. Self‐recording of study time in the absence of scheduled differential consequences did not improve test performance. Study rate under no‐consequence conditions varied with test schedule. For both consequence and no‐consequence groups, the correlation between study time and final score for the course was only moderate.

Rats bar pressing on a 1‐min fixed‐interval schedule for 45‐mg food pellets became Polydipsic when water was concurrently available. They were then exposed to conditions in which each lick on the drinking tube produced a timeout period during which the food‐schedule lever was retracted and the fixed‐interval timer either did or did not continue to operate. Licks occurring within a timeout period extended its duration. As the duration of the lick‐initiated timeout period was increased logarithmically through four values from 10 sec to 80 sec, lick rates as well as water intake rates generally decreased for all three subjects. As timeout duration was progressively increased, the rate of licks occurring in the absense of, but producing, timeouts decreased for all three rats, whereas the rate of licks occurring in the presence of timeout periods remained essentially constant. Water‐intake rates and, with one exception, lick rates were suppressed more by timeout periods during which the fixed‐interval timer did not continue to operate. These results indicate that lick‐contingent timeout from positive reinforcement reduces schedule‐induced drinking, and this suppressive effect is greater when the timeout period necessarily increases the interreinforcement interval beyond its minimum duration than when it does not.

Rats were exposed to a random sequence of reinforcement on two levers, such that there was no way to predict from the previous reinforcement which lever would deliver reinforcement next. The rats showed a tendency to repeat the choice that had just produced reinforcement, despite the absence of an overall contingency that differentially reinforced such repetition. However, this tendency decreased with continued exposure to the schedule. Runs of successive reinforcements on a lever increased the probability of pressing that lever, but only slightly, and only in the earlier phases of training. The more quickly a press was made after reinforcement the more likely it was to be on the lever that had delivered that reinforcement. Repetition of choice followed by reinforcement should be viewed as a naturally occurring behavior in the rat, but not necessarily as a behavior that will continue without differential reinforcement of repetition.

Rats' lever pressing was studied on three schedules of reinforcement: fixed interval, response‐initiated fixed interval, and fixed ratio. In testing, concentration of the milk reinforcer was varied within each session. On all schedules, duration of the postreinforcement pause was an increasing function of the concentration of the preceding reinforcer. The running rate (response rate calculated by excluding the postreinforcement pauses) increased linearly as a function of the preceding magnitude of reinforcement on fixed interval, showed slight increases for two of the three animals on response‐initiated fixed interval, and did not change systematically on fixed ratio. In all cases, the overall response rate either declined or showed no effect of concentration. The major effect of increasing the reinforcement magnitude was in determining the duration of the following postreinforcement pause, and changes in the response rate reflected this main effect.

Two experiments with human subjects investigated the effects of rate of reinforcement and reinforcer magnitude upon choice. In Experiment 1, each of five subjects responded on four concurrent variable‐interval schedules. In contrast to previous studies using non‐human organisms, relative response rate did not closely match relative rate of reinforcement. Discrepancies ranged from 0.03 to 0.43 (mean equal to 0.19). Similar discrepancies were found between relative amount of time spent responding on each schedule and the corresponding relative rates of reinforcement. In Experiment 2, in which reinforcer magnitude was varied for each of five subjects, similar discrepancies ranging from 0.05 to 0.50 (mean equal to 0.21), were found between relative response rate and relative proportion of reinforcers received. In both experiments, changeover rates were lower on the long‐interval concurrent schedules than on the short‐interval ones. The results suggest that simple application of previous generalizations regarding the effects of reinforcement rate and reinforcer magnitude on choice for variable‐interval schedules does not accurately describe human behavior in a simple laboratory situation.