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51.
Occlusion is a frequent occurrence in a cluttered world of opaque objects. Often information about the shape of partly occluded objects can be gathered from the visible portion of the object and in particular its contours. Here we address the case where a region of a surface is visible exclusively through an aperture (visual hole). We make several observations about the grouping of surface regions visible through holes, and the appearance of moving objects and holes. These observations support the view that holes are shape properties of the object-with-hole. 相似文献
52.
Custance D Prato-Previde E Spiezio C Rigamonti MM Poli M 《Journal of comparative psychology (Washington, D.C. : 1983)》2006,120(3):303-313
An artificial fruit (AF) was used to test for social learning in pig-tailed macaques (Macaca nemestrina) and adult humans (Homo sapiens). A monkey demonstrator opened the AF, showing alternative methods to 2 groups of cage mates. Video films of the monkey demonstrations were presented to adult humans. Compared with chimpanzees and children, the macaques watched the demonstrations significantly less and in a much more sporadic manner. They also produced only very weak and transitory evidence of social learning. In contrast, the adult humans performed as one might expect of optimum imitators, even producing evidence of components of a "ratchet effect." 相似文献
53.
The study aimed to investigate naïve beliefs regarding the dynamic and static behavior of reflections. In the first three experiments, participants in the study made predictions about the correspondence between real and reflected movements or about the orientation of the reflection of a static object placed in front of a mirror. In Experiments 1 and 2, paper-and-pencil tasks were used and in Experiment 3 participants were asked to make their predictions while imagining that they were facing a mirror. Results revealed that a percentage of undergraduates (ranging from 25% to 35%) were unable to make correct predictions. We classified the errors into types and found that responses either conform to the belief that reflections do the same or that they do the opposite. This suggests an oversimplification of the geometry of mirror reflections in two directions: participants either generalize what they see when movements are parallel to the mirror or what they see when movements are orthogonal to the mirror. Findings from Experiment 4 confirmed that these two expectations fit in with what people perceive in mirrors. Findings from Experiment 5 confirmed that this is also in agreement with the relationship perceived when looking at similar movements and orientations “outside” mirrors. 相似文献
54.
Marco Weber Willibald Ruch Hadassah Littman-Ovadia Shiri Lavy Or Gai 《Personality and individual differences》2013
We investigated relationships among five higher-order strengths factors, subjective well-being, and general self-efficacy in participants that live under challenging conditions. Therefore, a sample of 396 Israeli adolescents (aged 13–18 years) completed the Values in Action Inventory of Strengths for Youth, the Satisfaction With Life Scale, the Affect Balance Scale, and the General Self-Efficacy Scale. An orthogonally rotated principal component analysis of the 24 character strengths yielded five strengths factors that explained 32% of the variance in life satisfaction, with the transcendence strengths factor as the most substantial predictor. The strongest predictors of positive affect were the transcendence and leadership strengths factors; the best predictors of negative affect were the transcendence and temperance strengths factors; and the strongest predictor of affect balance was the transcendence strengths factor. The five strengths factors explained 46% of the variance in general self-efficacy, with the leadership strengths factor as the most substantial predictor. Further analysis indicated that general self-efficacy mediated the relationship between leadership strengths and global life satisfaction. The results suggest that different strengths factors are relevant for different positive experiences (e.g., life satisfaction, self-efficacy beliefs). The findings shed light on the contribution of specific character strengths as a meaningful resource under stressful conditions. 相似文献
55.
Marco Del Giudice 《Multivariate behavioral research》2013,48(4):571-573
In a previous paper (Del Giudice, 2017 [Heterogeneity coefficients for Mahalanobis' D as a multivariate effect size. Multivariate Behavioral Research, 52, 216–221]), I proposed two heterogeneity coefficients for Mahalanobis' D based on the Gini coefficient, labeled H and EPV. In this addendum I discuss the limitations of the original approach and note that the proposed indices may overestimate heterogeneity under certain conditions. I then describe two revised indices H2 and EPV2, and illustrate the difference between the original and revised indices with some real-world data sets. 相似文献
56.
Marco Giovanelli 《Synthese》2013,190(17):3819-3863
By inserting the dialogue between Einstein, Schlick and Reichenbach into a wider network of debates about the epistemology of geometry, this paper shows that not only did Einstein and Logical Empiricists come to disagree about the role, principled or provisional, played by rods and clocks in General Relativity, but also that in their lifelong interchange, they never clearly identified the problem they were discussing. Einstein’s reflections on geometry can be understood only in the context of his ”measuring rod objection” against Weyl. On the contrary, Logical Empiricists, though carefully analyzing the Einstein–Weyl debate, tried to interpret Einstein’s epistemology of geometry as a continuation of the Helmholtz–Poincaré debate by other means. The origin of the misunderstanding, it is argued, should be found in the failed appreciation of the difference between a “Helmholtzian” and a “Riemannian” tradition. The epistemological problems raised by General Relativity are extraneous to the first tradition and can only be understood in the context of the latter, the philosophical significance of which, however, still needs to be fully explored. 相似文献
57.
Arabic numerals are diffused and language-free representations of number magnitude. To be effectively processed, the digits composing Arabic numerals must be spatially arranged along a left-to-right axis. We studied one patient (AK) to show that left neglect, after right hemisphere damage, can selectively impair the computation of the spatial frames underpinning recognition and understanding of Arabic numerals, without impairing the spatial frames for coding alphabetic strings or for coding environmental spatial information. The presence in our brain of these specific and precise spatial frames must be rooted in the paramount importance of Arabic numerals processing in our everyday activities. 相似文献
58.
Marco Fabbri Nicola Cellini Monica Martoni Lorenzo Tonetti Vincenzo Natale 《Cognitive Science》2013,37(7):1228-1250
The spatial‐temporal association indicates that time is represented spatially along a left‐to‐right line. It is unclear whether the spatial‐temporal association is mainly related to a perceptual or a motor component. In addition, the spatial‐temporal association is not consistently found using a time reproduction task. Our rationale for this finding is that, classically, a non‐lateralized button for performing the task has been used. Using two lateralized response buttons, the aim of the study was to find a spatial‐temporal association in a time reproduction task. To account for the perceptual component, reference and target stimuli were presented in different spaces through four experiments. In all experiments, a Spatial‐Temporal Association of Response Codes (STEARC) effect was found and this effect was not modulated by the spatial position of both reference and target stimuli. The results suggested that the spatial‐temporal association was mainly derived from the spatial information provided by response buttons, reflecting a motor but not visuospatial influence. 相似文献
59.
Abstract A prospective study of 94 Dutch adults who have casual sexual partners examined whether two important aspects of safe sex, namely bringing up condom use (BCU) and actual condom use (ACU) are intentional or habitual. For each of these aspects, a model based on the Theory of Planned Behaviour (TPB: Ajzen, 1991) was pitted against a similar model that was extended with a path from past to later BCU and ACU, respectively. The results suggest that bringing up the issue of condom use was equally predicted by intentions and past BCU. However, among people with casual partners, using condoms - and more importantly not using condoms - was especially predicted by past ACU, suggesting a strong habitual component. These results are discussed in terms of their implications for safe sex education and the use of theories in safe sex promotion campaigns. 相似文献
60.
This study investigates the role of linguistic and visuospatial attentional processes in predicting reading fluency in typical Italian readers attending primary school. Tasks were administered to 651 children with reading fluency z scores > ?1.5 standard deviation to evaluate their phonological awareness, rapid automatized naming (RAN), verbal short-term memory, vocabulary, visual search skills, verbal-visual recall, and visual-spatial attention. Hybrid models combining confirmatory factor analysis and path analysis were used to evaluate the data obtained from younger (first and second grade) and older (third–fifth grade) children, respectively. The results showed that phonological awareness and RAN played a significant role among younger children, while also vocabulary, verbal short-term memory, and visuospatial attention were significant factors among older children. 相似文献