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101.
A program was designed to teach coin equivalence to mentally retarded adolescents. Coin equivalence was defined as choosing several different combinations of coins to equal specified target values. A pretest-posttest matched-groups design was employed with an experimental group receiving the monetary training, and a no-training control group. A multiple baseline across coin-counting responses was also incorporated in the experimental group. Training was divided into six stages, each teaching one specific method of combining coins to equal 10 target values from 5¢ through 50¢. A three-component response chain was used, requiring (a) naming, (b) selecting and counting, and (c) depositing target monetary values into a coin machine. Experimental subjects improved significantly in coin equivalence performance and maintained their skill on follow up tests; control subjects did not.  相似文献   
102.
Pigeons' key pecking resulted in food according to either a variable-ratio or a variable-interval schedule. At the same time, food was available for not pecking for a specified time. The required time of not-pecking was segmented into not-responding units, and these units were followed by food according to a fixed-ratio schedule. Both unit duration and the number required were varied. In general, the shorter the time unit or the smaller the ratio, the lower was response rate. When total required not-responding time was constant, but changes in unit duration and the number required altered how the total was achieved, shorter units produced lower rates. Other conditions involved substitution of food delivered independent of responding for the not-responding schedule. With low and moderate total times to food presentation, the not-responding schedule produced lower rates; with the longest times, the response-independent schedule generated less responding. When considered in terms of relative frequency of food presentation available from a source other than pecking, the not-responding schedule reduced rate more effectively than did the response-independent schedule. Comparisons with other research suggested that food presented dependent on not responding compared favorably with punishment as a procedure for reducing response rate. Transient effects differed. Although punishment temporarily depresses rate when first imposed and temporarily enhances it when first removed, food given for not responding quickly generated steady-state rates.  相似文献   
103.
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.  相似文献   
104.
The role of response-reinforcer contiguity on autoshaped key pecking in pigeons was studied by scheduling response-dependent nonreinforcement at the beginning or the end of brief (8-sec) discrete trials. Schedules that permitted chance conjunctions of key pecking and food sustained high rates of responding, whereas those that prevented the occurrence of key peck-food intervals shorter than 4 sec sustained low response rates. In addition, selective reinforcement schedules supported accelerating or decelerating rates of responding within individual trials. These effects were traceable to response-reinforcer (operant), but not stimulus-reinforcer (respondent) factors.  相似文献   
105.
Six pigeons were trained to discriminate between two noise intensities using a procedure that assessed choice, time allocation, and response rate simultaneously and independently. Responses on the left or right key (R1 or R2) were respectively correct in the presence of two different intensities, S1 and S2. After a correct response, reinforcement became available for pecks on the center key. Reinforcement density for R1¦S1 relative to R2¦S2 was varied across experimental conditions. Generalization tests followed extensive training at each condition. As a function of stimulus intensity, proportions of initial choices of R2, of time spent in R2-initiated components, and of center-key responses emitted in R2-initiated components all yielded sigmoidal gradients of similar slope, which shifted slightly in location when relative reinforcement density changed. Changeovers were maximal where initial choice proportions approximated 0.5. Gradients relating the absolute number of center-key responses to stimulus intensity were also roughly sigmoidal, but were more sensitive to changes in reinforcement density. Gradients of momentary response rate also depended on reinforcement density. During training, large but transitory shifts in choice responding occurred when reinforcement density changed, while differences in momentary response rate developed slowly, suggesting separate control of choice and response rate by the contingencies of reinforcement.  相似文献   
106.
Self-reinforcement in operant situations generally refers to those arrangements in which the subject delivers to himself a consequence, contingent on his behavior. However, it is noted that the definition of all other types of reinforcement make its delivery contingent on the subject's behavior. What is actually at issue is the agent who defines whether or not the response required for reinforcement has been met. In self-reinforcement, the subject himself defines this. In the laboratory, this requirement is machine-defined; in school examinations, it is teacher-defined; and in many clinical self-control situations, it is also independently defined. A reinforcement contingency presupposes such independence, absent in self-reinforcement. Implications for research and practice are discussed and alternative formulations are offered.  相似文献   
107.
Data representing high, medium, and low response rates in constant and nonconstant patterns were generated by electromechanical equipment to determine whether the same data collected by time-sampling, interval recording, and frequency recording would be represented similarly by each method. Results indicated: (1) that time-sampling provided an extremely inaccurate estimate of responding, and (2) that interval recording accurately represented responding of low and medium rates, but grossly underestimated high-rate responding.  相似文献   
108.
A reinforcement system utilizing instructions, modelling, feedback, and group reinforcement was employed in an attempt to reduce disruptive noise on three university residence halls. A fourth hall received the same treatment program without the reinforcement component. Noise scores were determined by recording the number of discrete noise occurrences over a criterion decibel level. On all four residential floors, noise scores during treatment conditions were lower than initial and final baseline levels. Additionally, periods of noise reduction corresponded to the changing criterion multiple-baseline and reversal designs utilized. Pre- and posttreatment questionnaire responses from the three reinforcement floors paralleled changes in objective noise data. At posttreatment, residents reported less noise disturbance of study and sleep and more control over the noise situation and floor problems in general. These results indicated that a comprehensive behavior-modification treatment package was effective in reducing disruptive noise in university residence halls. Difficulties in data collection and anomalies in the data are discussed. Future directions for field-based behavior-modification research are outlined.  相似文献   
109.
Six elementary school children served as subjects in an experiment comparing the relative effectiveness of (1) token reinforcement, in which children received tokens for attending and for correct arithmetic performance; (2) response cost, in which children received “free” tokens at the start of a period but lost them for inattention and for arithmetic performance below a specified level; and (3) a combination of both token reinforcement and response cost. During training, the six subjects received all three procedures in counterbalanced sequence. The effects of the three procedures were assessed by a within-subject comparison divided into three phases: (i) baseline, (ii) training, (iii) withdrawal of tokens. Introduction of the three token procedures markedly increased the two dependent measures. However, there were no differences across the procedures in the amount of change produced in either attending behavior or arithmetic performance. During baseline, the subjects averaged 29% attending behavior and 6.4 correct problems. These levels increased to 85% for attending behavior and 11.4 correct problems for arithmetic performance during training. Removal of all token procedures significantly decreased attending behavior (to an average of 65%), but produced a nonsignificant reduction in arithmetic performance (to an average of 7.6 correct problems). There was evidence that this lack of differential effects of the three token procedures was not due to an inability to discriminate among them. Furthermore, the subjects were evenly divided in their preference for the three procedures.  相似文献   
110.
Four rats responded on one-minute variable-interval schedules with several variations in peak-force of response required for food reinforcement. Measures of peak force and rate were taken for the responses, which were the downward exertions of force against a static force-transducing operandum. The analysis distinguished responses, a generic class of measured behavior, from criterion responses, an operationally specified subclass required for reinforcement. Absolute rate of response showed no systematic change, but the rate of responses meeting a newly required criterion of peak-force invariably increased through changes in the absolute rate of response, the relative-frequency distributions of peak force, or some combination of both. The relative frequency of responses meeting an elevated force criterion during variable-interval reinforcement exceeded that maintained with the same criterion with continuous reinforcement. The requirement of more effortful responding for reinforcement does not necessarily reduce response rate. Conformity of the behavior to the requirement for reinforcement is the salient effect.  相似文献   
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