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61.
An invisible displacement test was administered to cats in order to test the hypothesis that search behaviour in this species is influenced by their limited capacity for object permanence as well as by their previous experience with the environment. Experiment 1 compared three groups of cats in a five-choice hiding task in which the hiding places could be discriminated by their spatial positions. Two groups received a visible displacement training before the invisible displacement test and one group did not. Experiment 2 compared two groups of trained subjects in the same task, but the hiding places could be discriminated by spatial and visual cues. The results confirmed that cats are unable to solve problems with invisible displacements. The visible displacement training improved their performance, but was not sufficient to make them succeed. Experience with the hiding potential of the covers also gives more persistence to search behaviour. Finally, the distribution of search attempts is not determined by the proximity to the target and is influenced only partially by the subjects' previous experience. Like Stage 5 infants, cats rely mainly on their immediate perception. They search for an object in the last location they have seen it disappear or under the nearest cover from this location.  相似文献   
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We analyzed the role of the range of variation in training exemplars as a contextual variable influencing the effects of in vivo versus simulation training in producing generalized responding. Four mentally retarded adults received single case instruction, followed by general case instruction, on washing machine and dryer use; one task was taught using actual appliances (in vivo) and the other using simulation. In vivo and simulation training were counterbalanced across the two tasks for the 2 subject pairs, using a within-subjects Latin square design. With both paradigms, more errors were made after single case than after general case instruction during probe sessions with untrained washing machines and dryers. These results suggest that generalization errors were affected by the range of training exemplars and not by the use of simulated versus natural training stimuli. Although both general case simulation and general case in vivo training facilitated generalized performance of laundry skills, an analysis of training time and costs indicated that the former approach was more efficient. The study illustrates a methodology for studying complex interactions and guiding decisions on the optimal use of instructional alternatives.  相似文献   
63.
Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.  相似文献   
64.
How is meaning assigned to those terms in a theory which are remote from direct observational instantiation? Models and analogies play a role, but close examination of theories in high energy physics shows that the design of experimental apparatus also influences the interpretation of such terms. Certain apparatus favours certain kinds of effects, and this affects the way mathematical theories are interpreted. In particular track producing apparatus becomes involved with theories in which photonic terms are picked out in the theory. A further conceptual constraint is thus introduced. It is argued that this situation favours the interpretation of dispositional properties as affordances rather than as simple dispositions.  相似文献   
65.
The role accorded to the public by scientists and philosophers of science has undergone an essential historical change in the last three centuries. Public participation in (witnessing of) scientific experiments was considered an important requirement for 17th century experimenters (e.g. for Boyle or Pascal). The cognitive role played by lay persons was later substantially downgraded; witnessing went out of fashion, while science became more and more esoteric and a matter for experts only. Part of this process was that all scientific disciplines became intensively compartmentalized and in consequence a rather puzzling or even paradoxical situation appeared: that the scientists themselves were and are being reduced epistemically to the status of lay persons, outside of their proper field of expertise (as was pointed out by J. Hardwig). The paper deals with some cognitive aspects of this historical process.  相似文献   
66.
This paper evaluates three hypotheses about the structure of threat perceptions in the post-Cold War era: the replacement of a military conception of threat by an economic one; fluidity in threat perceptions because of an absence of a polestar nation; and Huntington's clash of civilizations theory. Using psychophysical magnitude measures of threat perception, these findings provide no support for the notion that threats are perceived economically. There is limited support for the theory that threat perceptions are unstable; most countries are clustered around a core of weakly hostile or friendly perceptions, which is suggestive of instability. At the same time, however, there does appear to be stability in perceptions of strong friends and enemies. The hypothesis best supported by these data is Huntington's theory that culture determines threat perceptions. In this study, not a single Western country is perceived as hostile, and all nations that do receive hostile scores are non-Western.  相似文献   
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This paper describes a research program on mentally retarded parents and their children. For this nation-wide study, two structured questionnaires were sent to all municipalities in Norway. Both questionnaires were sent to public health nurses and were followed-up by a structured telephone interview based on the questionnaires. The primary aim of the study was to survey the number of children born to mentally retarded parents. In addition, the children's needs and functional abilities were to be assessed. Twenty-three mentally retarded persons had given birth in the course of the past twelve months. A total of 126 children with mentally retarded parents were identified, with an incidence of 27 children per year, and a prevalence of approximately 430 children under 16 years of age in a population of 4 mill. People with a mean of 1.05 child per family. About 43% of the children of mentally retarded parents appeared to have learning difficulties. Forty percent of the children suffered from failures of care. Between 25% and 68% of the children with learning problems had poorly developed motor or language abilities, sense modalities or psycho-social status.  相似文献   
70.
This article presents research in which the Five Factor Model of personality was tested as a predictor of job performance. 125 financial services managers who had enrolled in a potential evaluation programme were given the NEO-FFI, a questionnaire designed for measuring the Big Five. Job performance was assessed using nine rating scales and they were grouped into two components: job problem-solving ability and job motivation. Also, one single scale for measuring global job performance was used. The results show that Neuroticism and Conscientiousness correlated with the two components and with the global measure of job performance. Extraversion, Openness and Agreeableness are correlated with one facet or with the global rating of job performance. Taken together, the results suggest that the Five Factor Model is a valid predictor of job performance. The implications of the results for practice and future research are discussed.  相似文献   
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