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971.
972.
The significance of a helicopter patrol procedure directed toward prevention of home burglaries was evaluated from experimental and cost-benefit perspectives. The helicopter patrolled one city zone from 9 a.m. to 5 p.m. for two 12-day periods. Each 12-day period was separated by a baseline period in which only normal patrol-car levels were maintained. Significantly reduced burglary levels during the intervention periods, compared to baseline periods, documented the experimental significance of the helicopter procedure. The cash costs of implementing the patrol procedure were compared to two estimates of the resulting cash benefits. This latter cost-benefit analysis was supplemented by a discussion of the intangible costs and benefits of the helicopter procedure. Taken together, these analyses documented that the marginal costs of the helicopter intervention were exceeded by all estimates of benefits.  相似文献   
973.
Previous research using French material and subjects has found that noun-adjective pairs are easier to recall than adjective-noun pairs, which suggests that linguistic rules are important in determining performance. However, experiments using English material have also suggested that noun-adjective phrases are easier, although in English these pairs violate grammatical conventions. The latter findings have been interpreted as supporting the view that mental imagery is important in remembering. However, these studies are faulty in various respects. In an experiment on free recall, using English material, the grammatical order (adjective-noun) was found to produce better performance than the reversed order (noun-adjective), but only because reversed phrases tended to be reported in the conventional order. This supports the original view that grammatical constraints affect recall.  相似文献   
974.
The current studies were designed to investigate the influence of variations in type of school setting on the development of role-taking skills and ethnic identity. We were interested in groups of school children in grades 1 to 5 inclusive from three different types of language programs: (1) instruction in the native language (English in this case); (2) total instruction in a second language (French); and (3) partial instruction in a second language (French). All children were native-English speaking, and came from perdominantly middle class families with monolingual English-speaking parents. The children from each program were equated at each grade level on age, and verbal and non-verbal I.Q. It was expected that (1) children in the second language programs would develop identity with their native language reference group later and less consistently than children in the native language programs; because (2) the second language children would identify more with the second language ethnic group; (3) the second language children would be able to understand at an earlier grade level than the native language group the principle of reciprocity in role-taking; and (4) these difference would be more pronounced for the totally than for the partially immersed second language children. The children were required to rate a number of ethnic dolls on a 20 point rating scale according to (1) how much each would be desired as a personal friend, (2) how much each would be desired as a friend for a member of another specific ethnic group, and (3) how similar each doll was to the child. The results indicated general support for hypotheses (1), (2) and (4), particularly among the primary school samples (1, 2), but a lack of support for hypothesis (3). These results demonstrate the influence of socio-cultural factors on the development of ethnic identity and ethnic role-taking skills.  相似文献   
975.
Four normal and four deviant children aged four-to-six years were taught to judge the quality of their academic work in a preschool classroom, and to prompt or cue their teachers to comment about the quality of that work. When these skills did not generalize spontaneously to other teachers in concurrent natural situations, generalized responding was taught by the experimenter, in multiple-baseline design across subjects. This generalization programming enabled the children to contact a sometimes dormant, but readily available natural community of teacher praise and reinforcement, i.e., to recruit an increase in cued praise and schedules of praise for their good work. These behaviors may be important to young children who find themselves bereft of attention in classrooms.  相似文献   
976.
An experiment was conducted to test the proposition that rewards undermine or enhance intrinsic interest in a task to the extent that individuals interpret their behavior as being motivated by the reward. It was predicted that when subjects were denied the opportunity to develop and confirm this attribution, rewards would not produce an undermining effect, but rather would enhance dispositions and behavior. Subjects were recruited to evaluate a new sugar-free soft drink. Two levels of incentives (reward-no reward), two levels of examination (opportunity-no opportunity), and three levels of outcome (good-neutral-poor) were employed. The results support the prediction that an incentive's effect depends on the examination opportunity. In the examination condition, rewarded subjects attributed their behavior more to external factors than did unrewarded subjects, but gave more negative product evaluations only after tasting it. In the no examination condition, there were no differences in the attributions made by rewarded and unrewarded subjects, and rewarded subjects were more positively disposed toward the product both before and after tasting it. These results are explained as a consequence of two properties of rewards, enhancement through reinforcement and undermining through discounting, and of hypothesis-testing processes.  相似文献   
977.
An incidental memory paradigm was used to study involuntary encoding processes and voluntary retrieval strategies in children's memory. Preschool (mean age: 4 years, 4 months) and kindergarten (mean age: 5 years, 10 months) children sorted pictures according to their color or category membership, and then received either a recall test (Experiment 1) or a recognition test (Experiment 2). Better retention of category- than color-sorted items was observed for kindergarten children in free recall, preschool and kindergarten children in cued recall, and neither group in recognition. These results were interpreted in terms of the retrieval strategies used by children in each of the memory tasks. The importance of distinguishing between voluntary and involuntary memory processes, and between acquisition and retrieval, in studies of depth-of-processing was emphasized. Developmental differences in performance appear to derive primarily from the role of voluntary search strategies in retrieval, rather than from age differences in involuntary encoding processes.  相似文献   
978.
This study compared black and white children on the Behavior Problem Checklist. Data on 1,162 white and 614 black children were obtained from school records and from teachers and were analyzed using multiple regression analysis of variance. Blacks were judged to have a greater frequency of behavior disorders than whites. A number of interactions of race with other variables were found, and their meanings were discussed.  相似文献   
979.
Discusses the process of observation and presents a systematic approach for incorporating behavioral observations into evaluations and written psychological reports. The approach is based on Robert Carkhuff's Human Resource Development Model, which combines the psychologist's attending and responding skills to explore where clients are, personalizing skills to understand where they need to be, and initiating skills to act on these goals. Using this framework and drawing on the experiences of the authors, several principles of report writing are discussed. The paper presents specific steps and skills which can be used to determine where a client is functioning in a variety of areas and to communicate this understanding to others. Examples are provided to illustrate the principles and steps described.  相似文献   
980.
Temporal control of behavior: schedule interactions   总被引:1,自引:1,他引:0       下载免费PDF全文
In Experiment I the response that terminated the postreinforcement pauses occurring under a fixed-interval 60-second schedule was reinforced, if the pause duration exceeded 30 seconds. The percentage of such pauses, rather than increasing, decreased. There were complex effects on the discriminative control of the pause by the reinforcer terminating the previous fixed interval, depending on whether the fixed interval and the added reinforcer were the same or different. In Experiments II(a) and II(b), each reinforcement initiated an alternative fixed-interval interresponse-time-greater-than-t-sec schedule, the schedule values being systematically varied. When the response following a pause exceeding a given duration was reinforced, fewer such pauses occurred than when they were not reinforced, i.e., on the comparable simple fixed-interval schedule. There was no systematic relationship between mean interrinforcement interval and duration of the postreinforcement pause. The pause duration initiated by reinforcement was directly related to the dependency controlling the shortest pause at that time, regardless of changes in mean interreinforcement interval.  相似文献   
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