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Previous studies of academic web interlinking have tended to hypothesise that the relationship between the research of a university and links to or from its web site should follow a linear trend, yet the typical distribution of web data, in general, seems to be a non-linear power law. This paper assesses whether a linear trend or a power law is the most appropriate method with which to model the relationship between research and web site size or outlinks. Following linear regression, analysis of the confidence intervals for the logarithmic graphs, and analysis of the outliers, the results suggest that a linear trend is more appropriate than a non-linear power law.  相似文献   
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A great obstacle for wider use of structural equation modeling (SEM) has been the difficulty in handling categorical variables. Two data sets with known structure between 2 related binary outcomes and 4 independent binary variables were generated. Four SEM strategies and resulting apparent validity were tested: robust maximum likelihood (ML), tetrachoric correlation matrix input followed by SEM ML analysis, SEM ML estimation for the sum of squares and cross-products (SSCP) matrix input obtained by the log-linear model that treated all variables as dependent, and asymptotic distribution-free (ADF) SEM estimation. SEM based on the SSCP matrix obtained by the log-linear model and SEM using robust ML estimation correctly identified the structural relation between the variables. SEM using ADF added an extra parameter. SEM based on tetrachoric correlation input did not specify the data generating process correctly. Apparent validity was similar for all models presented. Data transformation used in log-linear modeling can serve as an input for SEM.  相似文献   
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The use of R&D grants as a policy instrument has been motivated by economic arguments of market failure. Neo-classical econometric studies have analysed the additionality of one Euro of subsidies on both the investments of companies in the R&D process and the output of that R&D process. More recently, behavioural additionality has been launched as a third form of additionality. In contrast to input and output additionality, behavioural additionality is related to changes in the processes that take place within the firm. In this paper, we analyse the determinants of the behavioural additionality of R&D grants. To explain the mechanism through which behavioural additionality is obtained, we use organizational learning theory as a guide to formulate our hypotheses. Hypotheses are tested using a telephone survey of 192 recipients of R&D grants provided by the IWT in Flanders in 2001–2004, matched to a sample of 84 firms that undertake innovation activities but which had never had a grant bid accepted. We find that congenital learning and interorganizational learning lead to increased behavioural additionality. However, these learning effects decrease with the number of subsidized projects that are undertaken by the company.  相似文献   
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This paper asks two - relatively simple - questions: can cities shape socio-technical transitions? And how would we know if they were? There are three key objectives. The first of these is to set out emerging, and in our view, convincing evidence, that large world cities have political aspirations to develop purposive and managed change in the socio-technical organisation of infrastructure networks that can be characterised as ‘systemic’ transitions. The second objective is conceptual in orientation and seeks to address how we understand transitions at the scale of the city, the role of ‘the city’ in undertaking transitions, and review both the strengths and shortcomings of the multi-level perspective (MLP) on socio-technical transitions in addressing this. The third objective is to identify what an urban transition would look like, and then constructs a new framework to conceptualise and research urban transitions. The paper then summarises the key aspects and implications of our argument.  相似文献   
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Policy makers take initiatives to stimulate knowledge ecosystems in technology hotspots. It is implicitly assumed that these ecosystems will lead to value networks through which the participating companies can realize a competitive advantage. Value networks refer to business ecosystems where the value proposition is offered by a group of companies which are mutually complementary. The strategy literature suggests that business ecosystems lead to competitive advantages for each of the partners in the ecosystem. Based on a unique hand-collected database of 138 innovative start-ups in the region of Flanders, we analyze the knowledge and business ecosystem and the financial support network. We find that the knowledge ecosystem is well structured and concentrated around a number of central actors while the business ecosystem is almost non-existent at the local level. Further, we find that the financial support network is almost 100% publicly backed and fails to bridge the knowledge and business ecosystem. The implications for policy makers who tend to focus on the development of local ecosystems are discussed.  相似文献   
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The field of educational measurement has evolved considerably since the first doctoral programs were established. In response, programs have typically tacked on courses that address newly developed theories, methods, tools, and techniques. As our review of current programs evidences, this approach produces artificial distinctions among topics and techniques that are in fact a tightly coupled whole. This position paper advocates a redesign of the scope and sequence for doctoral programs focused on the preparation of the next generations of educational measurement specialists; a redesign that reflects the full life‐cycle of instrument development and use.  相似文献   
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While constructivism has made a considerable mark concerning learning in many areas of school learning, much less is evident relating to the education and professional development of teachers. This paper not only deals with the implementation and evaluation of such a constructivist course, but extends the argument towards the induction of teachers into “critical constructivism” through their own action research projects. Data is drawn from a single case study which illuminates the induction process and illustrates the changes taking place in the professional life and the reflective practice of one teacher as she deals with scientific concepts with two classes of 11–15 and 18–25 year olds. The Brazilian setting for the course lends resonance to its international significance.  相似文献   
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