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181.
"道"是老子哲学体系中的核心,老子不仅提出虚空的道是宇宙的本体,是无法用语言来描述的,而且说明道是混成之物,即道是有精妙的内部结构属性的,并从不同的侧面说明了认识"道"是混成之物的路径。道是由无限创生因子混融而成的系统,宇宙在创生及万物演化的过程中,道或无限的创生因子始终起着根本性的作用,即宇宙间的一切事物现象都是道所为。道是由创生因子混融而成的思想观点,可为现代宇宙论的发展提供新的思维维度,为科学探索真空世界的奥秘提供新的研究途径,推进现代宇宙学的进步。  相似文献   
182.
从表象加工水平角度考察引发错误记忆的因素。结果发现,深的表象加工水平能够抑制诱饵词产生较大的激活,减少错误记忆的发生。随着表象加工水平的加深,有意表象的错误记忆效应显著低于无意表象,而正确记忆效应则显著高于无意表象,表明表象加工水平对错误记忆具有重要影响。根据研究结果提出表象激活混淆假设,认为人们虽然可以用表象作为信息表征的方式,却无法直接获取与之联系的激活路径。当人们推测表象激活的来源时,容易混淆表象激活的来源,产生错误记忆。  相似文献   
183.
应用情绪版本的外部线索任务,以高中生为研究对象,探讨考试焦虑的产生是由负性刺激的警觉还是脱离困难导致的认知神经机制,以及这种注意偏向(警觉与脱离成分)发生的具体时间进程。行为实验结果发现,相比起低考试焦虑个体,高考试焦虑个体对考试相关威胁刺激存在注意脱离困难。脑电实验结果中,P1成分揭示高考试焦虑者对考试相关和无关威胁线索后靶刺激的注意处理削弱;考试相关威胁线索后靶刺激诱发的P300对于高、低考试焦虑者具有临床鉴别的潜力。  相似文献   
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185.
In this 8‐year longitudinal study, we traced the vocabulary growth of Chinese children, explored potential precursors of vocabulary knowledge, and investigated how vocabulary growth predicted future reading skills. Two hundred and sixty‐four (264) native Chinese children from Beijing were measured on a variety of reading and language tasks over 8 years. Between the ages of 4 to 10 years, they were administered tasks of vocabulary and related cognitive skills. At age 11, comprehensive reading skills, including character recognition, reading fluency, and reading comprehension were examined. Individual differences in vocabulary developmental profiles were estimated using the intercept‐slope cluster method. Vocabulary development was then examined in relation to later reading outcomes. Three subgroups of lexical growth were classified, namely high‐high (with a large initial vocabulary size and a fast growth rate), low‐high (with a small initial vocabulary size and a fast growth rate) and low‐low (with a small initial vocabulary size and a slow growth rate) groups. Low‐high and low‐low groups were distinguishable mostly through phonological skills, morphological skills and other reading‐related cognitive skills. Childhood vocabulary development (using intercept and slope) explained subsequent reading skills. Findings suggest that language‐related and reading‐related cognitive skills differ among groups with different developmental trajectories of vocabulary, and the initial size and growth rate of vocabulary may be two predictors for later reading development.  相似文献   
186.
Compared with the average consumer, market mavens possess a unique set of characteristics including a greater depth of knowledge of the marketplace and its products, as well as a strong social network. Based on a field study of an emerging social network of Canadian undergraduate students (N = 71), we examine the level of satisfaction and stress that market mavens experience as a result of their network participation. First, market mavens (versus non‐mavens) are more satisfied with their network if they occupy central network positions. Simultaneously, however, mavens incur more stress if they occupy these central positions. Further, market mavens have a lower rate of network growth and build a more a selective network of like‐minded others over time. This suggests that market mavens seek to interact with other market mavens more so than with non‐mavens about product‐related and market‐related information. Together, we provide new insights into the personal outcomes of market mavens' network positions and their networking behavior. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
187.
This paper demonstrates the usefulness and flexibility of the general structural equation modelling (SEM) approach to fitting direct covariance patterns or structures (as opposed to fitting implied covariance structures from functional relationships among variables). In particular, the MSTRUCT modelling language (or syntax) of the CALIS procedure (SAS/STAT version 9.22 or later: SAS Institute, 2010) is used to illustrate the SEM approach. The MSTRUCT modelling language supports a direct covariance pattern specification of each covariance element. It also supports the input of additional independent and dependent parameters. Model tests, fit statistics, estimates, and their standard errors are then produced under the general SEM framework. By using numerical and computational examples, the following tests of basic covariance patterns are illustrated: sphericity, compound symmetry, and multiple‐group covariance patterns. Specification and testing of two complex correlation structures, the circumplex pattern and the composite direct product models with or without composite errors and scales, are also illustrated by the MSTRUCT syntax. It is concluded that the SEM approach offers a general and flexible modelling of direct covariance and correlation patterns. In conjunction with the use of SAS macros, the MSTRUCT syntax provides an easy‐to‐use interface for specifying and fitting complex covariance and correlation structures, even when the number of variables or parameters becomes large.  相似文献   
188.
A pplications of standard item response theory models assume local independence of items and persons. This paper presents polytomous multilevel testlet models for dual dependence due to item and person clustering in testlet‐based assessments with clustered samples. Simulation and survey data were analysed with a multilevel partial credit testlet model. This model was compared with three alternative models – a testlet partial credit model (PCM), multilevel PCM, and PCM – in terms of model parameter estimation. The results indicated that the deviance information criterion was the fit index that always correctly identified the true multilevel testlet model based on the quantified evidence in model selection, while the Akaike and Bayesian information criteria could not identify the true model. In general, the estimation model and the magnitude of item and person clustering impacted the estimation accuracy of ability parameters, while only the estimation model and the magnitude of item clustering affected the item parameter estimation accuracy. Furthermore, ignoring item clustering effects produced higher total errors in item parameter estimates but did not have much impact on the accuracy of ability parameter estimates, while ignoring person clustering effects yielded higher total errors in ability parameter estimates but did not have much effect on the accuracy of item parameter estimates. When both clustering effects were ignored in the PCM, item and ability parameter estimation accuracy was reduced.  相似文献   
189.
While there is evidence that feedback projections from cortical and neuromodulatory structures to the olfactory bulb are crucial for maintaining the oscillatory dynamics of olfactory bulb processing, it is not clear how changes in dynamics are related to odor perception. Using electrical lesions of the olfactory peduncle, sparing output from the olfactory bulb while decreasing feedback inputs to the olfactory bulb, we demonstrate here a role for feedback inputs to the olfactory bulb in the formation of odor-reward associations, but not for maintaining primary bulbar odor representations, as reflected by spontaneous odor discrimination.  相似文献   
190.
A statistical manifold Mμ consists of positive functions f such that defines a probability measure. In order to define an atlas on the manifold, it is viewed as an affine space associated with a subspace of the Orlicz space LΦ. This leads to a functional equation whose solution, after imposing the linearity constrain in line with the vector space assumption, gives rise to a general form of mappings between the affine probability manifold and the vector (Orlicz) space. These results generalize the exponential statistical manifold and clarify some foundational issues in non-parametric information geometry.  相似文献   
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