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61.
62.
L'A. fait L'hypothèse que le dédoublement de la représentation, qui est caractéristique du style graphique de certaines cultures, provient d'une préférence universelle pour ce type de dessin chez les tout jeunes enfants de toutes cultures; mais dans la plupart des cultures, cette préférence serait supprimée parce que, paradoxalement, les dessins doubles ne permettent pas de reconnaître les objets dessinés aussi facilement que les dessins conventionnels qui sont plus proches de la projection rétinienne des objets. Les dessins avec enchaînement ou dédoublement de la représentation seraient conservés chaque fois qu'ils sont appréciés en tant que code utilisé à d'autres fins que L'information sur les objets peints et pour leur valeur esthétique.  相似文献   
63.
Procedures for determining logicality presuppose understanding, and procedures for determining understanding presuppose logic. One can escape from this circle only by presupposing logicality, in agreement with common-sense thinking. Understanding can then be studied as an empirical variable. Traditional research has been based on the opposite solution: Logicality is treated as an empirical variable, understanding is implicitly presupposed; hence results are obtained which do not 'make sense'. One cannot understand the illogical.  相似文献   
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Two groups of children, median ages 6–7 and 8–7, were presented with objects examplifying three combinations of two dichotomous attributes, and asked to indicate the remaining combination. Keeping objects covered vs. uncovered at the time of the test response had generally little effect. Labelling was consistently superior to perceptual matching, apparently because the latter involved a search process. The errors in the labelling condition consisted mostly in naming an object identical to or different in both attributes from those given, reflecting perhaps an inability to break down the impression of the objects into independent attributes.  相似文献   
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In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
68.
PIGEONS ARE SENSITIVE TO THE SPATIAL ORGANIZATION OF COMPLEX VISUAL STIMULI   总被引:1,自引:0,他引:1  
Abstract— Two experiments investigated the role of spatial organisation in the discrimination and generalization of complex visual stimuli by pigeons. In Experiment 1, after pigeons had been trained to discriminate line drawings of four objects, they were tested with novel pictures in which the same component parts of the objects were spatially rearranged. The spatially scrambled pictures led to a dramatic drop in recognition accuracy, hut responding remained above chance. In Experiment 2, pigeons reached a high level of discriminative performance when required to choose among four different spatial arrangements of the same object parts. These results confirm Cerella's (1980) conclusion that pigeons discriminate the component parts of complex visual stimuli, but. unless it is assumed that the scrambling deleted or created emergent features, the results disconfirm his conclusion that spatial organization plays no role in pigeons' picture perception.  相似文献   
69.
Uncertain knowledge about continuous quantities is usually formalized through subjective probability distributions (SPD′s). However, results from past experimental research have often pointed to the rather poor quality of SPD′s. Moreover, previous attempts to improve SPD quality frequently appeared to be only partly successful; overconfidence especially proved to be an exceptionally persistent phenomenon. In the present study, method-induced biases in particular are considered to be responsible for the poor quality of SPD′s, and an alternative means for eliciting uncertain knowledge was designed to meet fundamental quality criteria to a more satisfactory degree. The direct realization of a proper scoring rule in a graphically oriented interactive computer program is one of the central features of this new elicitation technique, ELI. An experiment with 48 subjects was carried out to evaluate ELI performance and to compare it with the performance of (a) an existing elicitation technique and (b) a simple technique that only asks for a best guess and a lower and upper bound. The three techniques were evaluated and compared with respect to their contribution to reliable and valid SPD′s and with respect to their practical usefulness. The results indicated that for ELI the fundamental requirements were realized to a great extent. Furthermore, compared with the two other techniques, ELI performance appeared to be superior. In particular, only with the support of ELI did overconfidence appear to be almost absent.  相似文献   
70.
The current study tests for the presence of differential order effects in evaluation tasks with consistent and inconsistent evidence as predicted by the Hogarth and Einhorn (1992) belief-adjustment model. The results, based on both between-subjects and within-subjects experiments, demonstrate that there were significant recency effects with inconsistent evidence as predicted, larger recency effects when the inconsistent evidence was farther apart in subjective value as predicted, and significant recency effects even when subjects were given training designed to both help them understand the task as completely as possible and to be better able to assess the pieces of evidence. By including a within-subjects design, we were able to demonstrate that the difference in subjective value between two pieces of evidence is the primary factor influencing the magnitude of the recency effect, regardless of whether the evidence is consistent or inconsistent. This latter finding is unique and contrary to previous research and theory.  相似文献   
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