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941.
We examine some assumptions about the nature of ‘levels of reality’ in the light of examples drawn from physics. Three central assumptions of the standard view of such levels (for instance, Oppenheim and Putnam 1958) are (i) that levels are populated by entities of varying complexity, (ii) that there is a unique hierarchy of levels, ranging from the very small to the very large, and (iii) that the inhabitants of adjacent levels are related by the parthood relation. Using examples from physics, we argue that it is more natural to view the inhabitants of levels as the behaviors of entities, rather than entities themselves. This suggests an account of reduction between levels, according to which one behavior reduces to another if the two are related by an appropriate limit relation. By considering cases where such inter-level reduction fails, we show that the hierarchy of behaviors differs in several respects from the standard hierarchy of entities. In particular, while on the standard view, lower-level entities are ‘micro’ parts of higher-level entities, on our view, a system’s macro-level behavior can be seen as a (‘non-spatial’) part of its micro-level behavior. We argue that this second hierarchy is not really in conflict with the standard view and that it better suits examples of explanation in science.  相似文献   
942.
Infants' ability to represent objects has received significant attention from the developmental research community. With the advent of eye-tracking technology, detailed analysis of infants' looking patterns during object occlusion have revealed much about the nature of infants' representations. The current study continues this research by analyzing infants' looking patterns in a novel manner and by comparing infants' looking at a simple display in which a single three-dimensional (3D) object moves along a continuous trajectory to a more complex display in which two 3D objects undergo trajectories that are interrupted behind an occluder. Six-month-old infants saw an occlusion sequence in which a ball moved along a linear path, disappeared behind a rectangular screen, and then a ball (ball-ball event) or a box (ball-box event) emerged at the other edge. An eye-tracking system recorded infants' eye-movements during the event sequence. Results from examination of infants' attention to the occluder indicate that during the occlusion interval infants looked longer to the side of the occluder behind which the moving occluded object was located, shifting gaze from one side of the occluder to the other as the object(s) moved behind the screen. Furthermore, when events included two objects, infants attended to the spatiotemporal coordinates of the objects longer than when a single object was involved. These results provide clear evidence that infants' visual tracking is different in response to a one-object display than to a two-object display. Furthermore, this finding suggests that infants may require more focused attention to the hidden position of objects in more complex multiple-object displays and provides additional evidence that infants represent the spatial location of moving occluded objects.  相似文献   
943.
Fallibilism is ubiquitous in contemporary epistemology. I argue that a paradox about knowledge, generated by considerations of truth, shows that fallibilism can only deliver knowledge in lucky circumstances. Specifically, since it is possible that we are brains‐in‐vats (BIVs), it is possible that all our beliefs are wrong. Thus, the fallibilist can know neither whether or not we have much knowledge about the world nor whether or not we know any specific proposition, and so the warrant of our knowledge‐claims is much reduced and second‐order skepticism is generated. Since this is the case in both skeptical and everyday contexts, contextualism cannot resolve the paradox.  相似文献   
944.
945.
Although new venture success is frequently investigated in entrepreneurship, economics, and psychology, the studies published to date vary widely in their theoretical basis, study design, and research methodology. Based on organizational life‐cycle theory and interactional personality theory, this longitudinal study analyses predictors of venture survival. Of 354 small business owners observed over 8 years, 283 (79.9%) still had active businesses at the end of the observation period. A survey instrument was developed to measure the relevant characteristics of the entrepreneurs, their resources, and the environment. Logistic regression models predicting medium‐ and long‐term business survival included these characteristics and the interactions between them entered stepwise as blocks. Startup decisions (line of business, type, and size of planned business) were used as control variables. Much of the variance is explained by our research model (Nagelkerkes R2=.36 for survival at 4 years, and .33 for survival at 8 years). Although long‐term business survival is predicted by the individual variables of startup size and social capital (networks), a larger part of the variance is explained by environment/resource interactions.  相似文献   
946.
The relationship between reaction time and both state and trait personality variables was investigated in 37 participants after 30 h of sleep deprivation. Regression analyses suggested that endorsement of greater Novelty Seeking, anger/hostility, and depression/dejection, and less confusion, was associated with greater reaction time declines on one Multi-Attribute Task Battery index after sleep deprivation. Further, greater Novelty Seeking and depression/dejection, and less vigor/activity, was associated with greater reaction time declines after sleep deprivation on another Multi-Attribute Task Battery index. Additional correlational analyses indicated that better reaction times were associated with greater Novelty Seeking and lower anger/hostility prior to sleep deprivation, and less confusion/bewilderment following sleep deprivation. Findings suggest that both state and trait personality variables are associated with reaction time performance following sleep deprivation.  相似文献   
947.
In masked priming tasks responses are usually faster when prime and target require identical rather than different responses. Previous research has extensively manipulated the nature and number of response-affording stimuli. However, little is known about the constraints of masked priming regarding the nature and number of response alternatives. The present study explored the limits of masked priming in a six-choice reaction time task, where responses from different fingers of both hands were required. We studied participants that were either experts for the type of response (skilled typists) or novices. Masked primes facilitated responding to targets that required the same response, responses with a different finger of the same hand, and with a homologous finger of the other hand. These effects were modulated by expertise. The results show that masked primes facilitate responding especially for experts in the S–R mapping and with increasing similarity of primed and required response.  相似文献   
948.
The objective of this study was to examine associations between specific dimensions of the multi-dimensional cumulative risk index (CRI) and asthma morbidity in urban, school-aged children from African American, Latino and Non-Latino White backgrounds. An additional goal of the study was to identify the proportion of families that qualify for high-risk status on each dimension of the CRI by ethnic group. A total of 264 children with asthma, ages 7–15 (40% female; 76% ethnic minority) and their primary caregivers completed interview-based questionnaires assessing cultural, contextual, and asthma-specific risks that can impact asthma morbidity. Higher levels of asthma-related risks were associated with more functional morbidity for all groups of children, despite ethnic group background. Contextual and cultural risk dimensions contributed to more morbidity for African-American and Latino children. Analyses by Latino ethnic subgroup revealed that contextual and cultural risks are significantly related to more functional morbidity for Puerto Rican children compared to Dominican children. Findings suggest which type of risks may more meaningfully contribute to variations in asthma morbidity for children from specific ethnic groups. These results can inform culturally sensitive clinical interventions for urban children with asthma whose health outcomes lag far behind their non-Latino White counterparts.  相似文献   
949.
Background. Recent literature on emotions in education has shown that competence‐ and value‐related beliefs are important sources of students' emotions; nevertheless, the role of these antecedents in students' daily functioning in the classroom is not yet well‐known. More importantly, to date we know little about intra‐individual variability in students' daily emotions. Aims. The objectives of the study were (1) to examine within‐student variability in emotional experiences and (2) to investigate how competence and value appraisals are associated with emotions. It was hypothesized that emotions would show substantial within‐student variability and that there would be within‐person associations between competence and value appraisals and the emotions. Sample(s). The sample consisted of 120 grade 7 students (52%, girls) in 5 randomly selected classrooms in a secondary school. Method. A diary method was used to acquire daily process variables of emotions and appraisals. Daily emotions and daily appraisals were assessed using items adapted from existing measures. Results. Multi‐level modelling was used to test the hypotheses. As predicted, the within‐person variability in emotional states accounted for between 41% (for pride) and 70% (for anxiety) of total variability in the emotional states. Also as hypothesized, the appraisals were generally associated with the emotions. Conclusions. The within‐student variability in emotions and appraisals clearly demonstrates the adaptability of students with respect to situational affordances and constraints in their everyday classroom experiences. The significant covariations between the appraisals and emotions suggest that within‐student variability in emotions is systematic.  相似文献   
950.
Despite the ubiquity and importance of metaphor in thought and communication, its neural mediation remains elusive. We suggest that this uncertainty reflects, in part, stimuli that have not been designed with recent conceptual frameworks in mind or that have been hampered by inadvertent differences between metaphoric and literal conditions. In this article, we begin addressing these shortcomings by developing a large, flexible, extensively normed, and theoretically motivated set of metaphoric and literal sentences. On the basis of the results of three norming studies, we provide 280 pairs of closely matched metaphoric and literal sentences that are characterized along 10 dimensions: length, frequency, concreteness, familiarity, naturalness, imageability, figurativeness, interpretability, valence, and valence judgment reaction time. In addition to allowing for control of these potentially confounding lexical and sentential factors, these stimuli are designed to address questions about the role of novelty, metaphor type, and sensory-motor grounding in determining the neural basis of metaphor comprehension. Supplemental data for this article may be downloaded from http://brm.psychonomic-journals .org/content/supplemental.  相似文献   
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