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A caseload analysis was undertaken to investigate those clients seen by five community mental health centre teams within one healthcare district. The 985 clients are described in terms of demographic and clinical features and questions relating to service provision are discussed. 相似文献
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Evidence increasingly links a high-fat, low-fiber diet to coronary heart disease and certain site cancers, indicating a need for large-scale dietary change. Studies showing the effectiveness of particular procedures in specific settings are important at this point. The present study, using an A-B-A-B design and sales data from computerized cash registers, replicated and extended previous work by showing that inexpensive prompts (i.e., signs and fliers) in a national fast-food restaurant could increase the sales of salads, a low-fat, high-fiber menu selection. Suggestions also are made pertinent to more widespread use of the procedures. 相似文献
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Typical delay determines waiting time on periodic-food schedules: Static and dynamic tests 总被引:6,自引:6,他引:0
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Pigeons and other animals soon learn to wait (pause) after food delivery on periodic-food schedules before resuming the food-rewarded response. Under most conditions the steady-state duration of the average waiting time, t, is a linear function of the typical interfood interval. We describe three experiments designed to explore the limits of this process. In all experiments, t was associated with one key color and the subsequent food delay, T, with another. In the first experiment, we compared the relation between t (waiting time) and T (food delay) under two conditions: when T was held constant, and when T was an inverse function of t. The pigeons could maximize the rate of food delivery under the first condition by setting t to a consistently short value; optimal behavior under the second condition required a linear relation with unit slope between t and T. Despite this difference in optimal policy, the pigeons in both cases showed the same linear relation, with slope less than one, between t and T. This result was confirmed in a second parametric experiment that added a third condition, in which T + t was held constant. Linear waiting appears to be an obligatory rule for pigeons. In a third experiment we arranged for a multiplicative relation between t and T (positive feedback), and produced either very short or very long waiting times as predicted by a quasi-dynamic model in which waiting time is strongly determined by the just-preceding food delay. 相似文献
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Rats were allowed to forage in a simulated natural environment made up of eight food sources (patches) each containing a fixed number of pellets. Two of the eight contained an extra supply of peanuts. The peanut patches were signaled by an olfactory/visual cue located at the bottom of the ladder leading to the patch. In successive phases the number of sessions per day, height of the patches, and availability of peanuts were manipulated. Subjects showed evidence of discrimination learning under these conditions, although the degree of discriminatory behavior varied as a function of environmental manipulations. Assessment of behavior within foraging sessions showed that subjects systematically changed their patterns of utilization of patches across time. Sampling or exploration, as well as food reinforcement, seem implicated in these results. 相似文献
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The present experiments were designed to teach pigeons to discriminate two locations represented by color photographs. Two sets of photographs were taken at two distinctive locations on a university campus. These sets represented several standpoints at each location. For the true-discrimination group, pictures from the two locations were differentially associated with reward; for the pseudodiscrimination group, half of the views from each location were arbitrarily but consistently associated with reward. The former group acquired the discrimination much more rapidly. These birds also showed good transfer to new views from the standpoints used in training and to a new standpoint at each location not used in training. In a second experiment, another group of pigeons could terminate any training trial by pecking an “advance” key. Three of 4 subjects used this option to reduce the duration of trials in which pictures from the negative location were presented. These data suggest that pigeons can integrate views shown in pictures into a “concept” of a location. The method used here may be the experimental analogue of a common, natural process by which animals learn to identify locations. 相似文献
8.
Hanna ES Blackman DE Todorov JC 《Journal of the experimental analysis of behavior》1992,58(2):335-347
Six experimentally naive pigeons were exposed to concurrent variable-interval variable-interval schedules in a three-key procedure in which food reinforcement followed pecks on the side keys and pecks on the center key served as changeover responses. In Phase 1, 3 birds were exposed to 20 combinations of five variable-interval values, with each variable-interval value consistently associated with a different color on the side keys. Another 3 pigeons were exposed to the same 20 conditions, but with a more standard procedure that used a nondifferential discriminative stimulus on the two side keys throughout all conditions. In Phase 2, the differential and nondifferential stimulus conditions were reversed for each pigeon. Each condition lasted for one 5-hr session and one subsequent 1-hr session. In the last 14 conditions of each phase, the presence of differential discriminative stimuli decreased the time necessary for differential responding to develop and increased the sensitivity of behavior to reinforcement distribution in the 1st hr of training; during the last hours of training in each condition, however, the effects of the differential discriminative stimuli could not be distinguished from the effects of reinforcement distribution per se. These results show the importance of studying transitions in behavior as well as final performance. They may also be relevant to discrepancies in the results of previous experiments that have used nonhuman and human subjects. 相似文献
9.
Fleming R 《Journal of applied behavior analysis》1992,25(3):611-620
To test the feasibility and utility of involving peers as sources of feedback, 6 subjects, instructors in a vocational program for adults with mental retardation, participated in a staff training and management program. Subjects' teaching interactions were assessed during baseline, in-service training (on effective teaching), return-to-baseline, peer management, and follow-up phases. Peer management was introduced in multiple baseline fashion across pairs of subjects. Members of each pair were trained to monitor peer teaching, to record and graph data, to provide feedback, and to set goals with the peer. Each pair then performed these procedures on the job for several weeks, during which time 4 of the 6 subjects increased their use of effective teaching methods (over baseline). However, inconsistencies in the magnitude and durability of these increases require that the study be viewed as inconclusive, although it has heuristic value as a promising model for involving co-workers in staff management programs. 相似文献
10.
John W. Schuster Ed.D. Ann K. Griffen B.S. Mark Wolery Ph.D. 《Journal of Behavioral Education》1992,2(3):305-325
Simultaneous prompting (a type of antecedent prompt and test procedure) and constant time delay were compared with four students with moderate mental retardation learning expressive sight words. A parallel treatments design across word sets and replicated across students was used. For acquisition, the simultaneous prompting procedures required fewer trials, sessions, and training time to criterion and resulted in fewer student errors during daily probe and training sessions. However, maintenance data indicated mixed results across the two procedures. Reliability data (both dependent and independent variables) revealed no differences between the two procedures in terms of the teacher's accuracy in recording student responses and implementing each procedure. Future research issues are discussed. 相似文献