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11.
Abstract In the present study, we investigated the accuracy of offside judgements of assistant referees in the English Premier League. The moment in the match, the position and movement speed of the assistant referee, attacker and second-last defender, together with the angle of view for the assistant referee were all considered to underlie incorrect decisions. The error rate was 17.5% (868 of 4960 situations). As the English assistant referees tended not to signal in doubtful situations (c = 0.91), there was an overall bias towards non-flag errors (773 non-flag errors vs. 95 flag errors). The flash-lag hypothesis could explain all flag errors, whereas the optical-error hypothesis could explain a proportion of the non-flag errors (45.4%). Fatigue, movement speed, and angle of view did not have a detrimental effect on offside decision making. In conclusion, there were fewer flag errors than in the 2002 and 2006 FIFA World Cups, whereas the number of non-flag errors rose. The increased awareness of factors involved in offside decision making and the instructions to give the benefit of the doubt to attackers could have contributed to this situation. 相似文献
12.
This study provides insight in the variety of urban-related challenges that beginning teachers experience in urban schools. Literature on urban teaching focuses on teaching children from low socio-economic status (SES) and/or culturally diverse backgrounds. In many European cities, however, schools are populated by both children from relatively high and from low-SES backgrounds. This study examined the problems and challenges of beginning teachers in Dutch urban primary schools. Teachers were interviewed at schools with different student populations. Results showed that, although many of the challenges that beginning teachers experienced concern the same themes, their actual manifestation differed related to schools’ student populations. For instance, the problem of ‘parental contact’ referred to both the extreme involvement and demands of highly educated wealthy parents at some schools and the diverse backgrounds of parents at other schools. Results of the study can be used to develop adequate preparation and support for beginning urban teachers. 相似文献
13.
In this paper, an explanatory program understander that can analyse student solutions for programming assignments is described. The approach uses a number of reverse engineering techniques and is grounded on a cognitive model of procedural programming knowledge. It will be shown that, through the use of reverse engineering techniques, a lot of feedback (e.g. on errors) can be generated without having to use any prior knowledge on what the program is supposed to do. When such information is available, problem-specific feedback can also be generated. Furthermore, the use of the cognitive programming concepts allows one to specify the errors in an understandable way using exactly the same words and concepts as human programmers. This opens interesting possibilities for other uses of the proposed program understanding technique described in this article. 相似文献
14.
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
15.
Most research related to learning in groups focuses on the unit of the group and/or group members. However, students may benefit from crossing the boundaries of their own group, as students in different groups may provide access to new, nonredundant knowledge and opportunities for learning. Whether boundary crossing between groups is beneficial for learning and academic performance has received limited conceptual and empirical attention. Using social network analysis and structural equation modeling, we contrasted pre/post network developments among 693 students (132 groups) across 4 modules at a UK business school. We examined whether it is better for students to invest in social relations in groups to learn and enhance academic performance or to (continue to) invest in social relations outside groups. Our findings indicated that students seemed to learn more from learning relations outside their group than from their own group members. Students with more intergroup relative to intragroup learning relations performed better on module assessments and throughout the academic year than students with more intragroup learning relations. Boundary crossing and intergroup learning deserves more empirical attention and experimentation on how to balance boundary crossing and effective group learning strategies. 相似文献
16.
Mikołaj Kozakiewicz 《Prospects》1986,16(3):327-336
17.
Creating value in ecosystems: Crossing the chasm between knowledge and business ecosystems 总被引:1,自引:0,他引:1
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
18.
Exploration and exploitation in innovation systems: The case of pharmaceutical biotechnology 总被引:2,自引:0,他引:2
This paper develops a theoretical framework for an explanation of how exploitation and exploration build on each other, in a ‘cycle of discovery’, developed in earlier research. The framework is tested empirically, in the sense of seeing whether it can help to reconstruct and understand the emergence of the pharmaceutical industry. One of the conclusions is that whereas recent literature stresses the idiosyncratic nature of the biotechnological revolution, our analysis seems to reveal that this does not seem to be as unique as suggested. From this, we conclude that the theoretical framework we propose, serves its purpose of explanation. But there are also some lessons for improving it. 相似文献
19.
Twice a year, the National Library of Medicine and Marine Biological Laboratory co-sponsor a fellowship in Biomedical Informatics for librarians, clinicians, and other health professionals in Woods Hole, MA. The fellowship is designed to inspire participants to become "agents of change" at their institution and to broaden their scope of knowledge for biomedical informatics. This paper discusses the field of biomedical informatics and explores the results of an informal survey from the librarians who participated in the fall session of 2005. 相似文献
20.