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991.
Discussion of open innovation has typically stressed the benefits to the individual enterprise from boundary-spanning linkages and improved internal knowledge sharing. In this paper we explore the potential for wider benefits from openness in innovation and argue that openness may itself generate positive externalities by enabling improved knowledge diffusion. The potential for these (positive) externalities suggests a divergence between the private and social returns to openness and the potential for a sub-optimal level of openness where this is determined purely by firms’ private returns. Our analysis is based on Irish plant-level panel data from manufacturing industry over the period 1994–2008. Based on instrumental variables regression models our results suggest that externalities of openness in innovation are significant and that they are positively associated with firms’ innovation performance. We find that these externality effects are unlikely to work through their effect on the spread of open innovation practices. Instead, they appear to positively influence innovation outputs by either increasing knowledge diffusion or strengthening competition. Our evidence on the significance of externalities from openness in innovation provides a rationale for public policy aimed at promoting open innovation practices among firms.  相似文献   
992.
In this article, we seek to unpack and enrich the notion of the design concept. We do this through the use of Gilles Deleuze and Felix Guattari's ‘concept’ in its philosophical specificity to critique less‐effective uses of the design concept. In particular, we investigate the idea that a concept is actually an aggregation of many concepts that can be seen to have a virtual consistency as a way to reframing more limited, typical, design concepts – used as justification, explanation, clarification or excuse. Our interest here is to explore how concepts can become much more useful throughout the process of design by drawing linkages between the concept and the workings of the creative process itself. In other words, we see the concept, parsed philosophically, as fusing with design thinking; and by taking advantage of this coupling each strengthens the other. Ultimately, we claim that a richer view of language and a more perfomative processes of making (diagramming) drive this coupling; and when it is working, the design concept becomes a much more useful instrument for designing.  相似文献   
993.
This paper is based on 1001 home‐based interviews with UK adults. It describes their varying patterns of participation in lifelong learning and their use of technology for learning and leisure. It finds that 37% of all adults report no further education of any kind after reaching compulsory school leaving age. This proportion declines with each age cohort, but is largely replaced by a pattern of lengthening initial education and still reporting no later education. These patterns of participation are predictable to a large extent from regression analysis using a life‐order model of determining variables—all of which are set very early in life. This suggests that universal theories to describe participation, such as human capital theory, are incorrect in several respects. Where individuals create, for themselves and through their early experiences, a ‘learner identity’ inimicable to further study, then the prospect of learning can become a burden rather than an investment for them. This has implications for the now widespread and extensively funded notion of overcoming barriers to access via technology.  相似文献   
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The present article considers a fundamental question in evaluation research: “By how much do program effects vary across sites?” The article first presents a theoretical model of cross-site impact variation and a related estimation model with a random treatment coefficient and fixed site-specific intercepts. This approach eliminates several biases that can arise from unbalanced sample designs for multisite randomized trials. The article then describes how the approach operates, explores its assumptions, and applies the approach to data from three large welfare-to-work trials. The article also illustrates how to report cross-site impact findings and presents diagnostics for assessing these findings. To keep the article manageable, it focuses on experimental estimates of effects of program assignment (effects of intent to treat), although the ideas presented can be extended to analyses of multisite quasi-experiments and experimental estimates of effects of program participation (complier average causal effects).  相似文献   
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This paper describes briefly a methodology for developing multiple-choice critical thinking tests which attempts to overcome certain problems of validity and fairness facing such tests. The paper proposes that direct evidence on test validity be gathered using verbal reports of students' thinking on trial items.  相似文献   
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Query Expansion with Long-Span Collocates   总被引:1,自引:0,他引:1  
The paper presents two novel approaches to query expansion with long-span collocates—words, significantly co-occurring in topic-size windows with query terms. In the first approach—global collocation analysis—collocates of query terms are extracted from the entire collection, in the second—local collocation analysis—from a subset of retrieved documents. The significance of association between collocates was estimated using modified Mutual Information and Z score. The techniques were tested using the Okapi IR system. The effect of different parameters on performance was evaluated: window size, number of expansion terms, measures of collocation significance and types of expansion terms. We present performance results of these techniques and provide comparison with related approaches.  相似文献   
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