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941.
942.
943.
Social loafing refers to the tendency for individuals to reduce their own personal input when performing as part of group. This phenomenon may be problematic if it exists in educational contexts, given a current emphasis on group collaborative classroom activities. The present study investigated whether social loafing existed in a collaborative educational task, employing groups of three and eight participants. The results indicated that individuals working within the smaller groups were more productive than those working in larger groups, consistent with the social loafing hypothesis. Future research should determine whether the detrimental effects on students' collaborative performance attributable to social loafing are justifiable in terms of gains accrued in other (e.g. interpersonal) domains. 相似文献
944.
Coopetition, i.e., cooperation between competing actors, has become a pervasive strategy for innovative firms. The primary focus of studies investigating coopetition centers on inter-firm relationships, highlighting the benefits, limits and configurational patterns of cooperative relationships between competing firms. Only a small, emerging group of studies seeks to extend the concept to the intra-firm level, stressing the existence and effects of competition and cooperation between units that are part of the same organization. This paper contributes to this latter group by investigating the effects of internal coopetition on knowledge and innovation sharing and highlighting the fundamental role of knowledge brokers in managing the resulting tensions. Based on a qualitative case study of the video game publisher Ubisoft, we stress how the tensions raised by internal coopetitive settings limit knowledge sharing between units, and we analyze the mechanisms through which the knowledge broker helps to overcome these limits. We identify three main functions of this knowledge broker that allow the promotion of knowledge and innovation transfer to occur between coopeting units: (1) protecting the unit’s competitive advantage by introducing a lagging principle in the transfer process, (2) reducing sharing costs by standardizing innovative solutions, and (3) enhancing awareness of and trust in innovative solutions by centralizing knowledge diffusion. 相似文献
945.
Joan L. Whipp R. A. Lorentz 《Educational technology research and development : ETR & D》2009,57(2):169-192
While literature suggests that college students may be less reluctant to seek help in online rather than traditional courses,
little is known about how online instructors give help in ways that lead to increased student help seeking and academic success.
In this study, we used theories and research on learning assistance and scaffolding, teacher immediacy, social presence, and
academic help seeking to explore through a cross-case study design how three online instructors differed in their use of cognitive
and social supports and how those differences related to student perceptions of support, help seeking, and performance. Primary
data sources included all course postings by the instructors, interviews with the instructors, observational field notes on
course discussions, student interviews, and final student grades. Archived course documents and student discussion postings
were secondary data sources. Data analysis revealed that while all instructors provided cognitive and social support, they
varied in their level of questioning, use of direct instruction, support for task structuring, and attention to group dynamics.
This variation in teaching presence related to differences across the courses in student perceptions of support, student help
seeking in course discussions, and final course grades. Implications for online teaching and suggestions for further research
are offered.
相似文献
Joan L. WhippEmail: |
946.
27 children with early onset (less than 4 years) diabetes (EOD), 24 with late onset (greater than 4.0 years) diabetes (LOD), and 30 sibling controls were compared in their performance on tests of intellectual functioning and school achievement. The results indicated that children with EOD, particularly girls, scored lower than the other groups of diabetic children and siblings on tests of visuospatial but not verbal ability. Many of the children with EOD were also having difficulty at school, and a number were currently receiving special education. Diabetic children with earlier onset had more hypoglycemic convulsions than those with later onset. Regression analyses revealed that duration of illness, age of onset, and hypoglycemic convulsions significantly predicted spatial ability. 相似文献
947.
Michael Silver Chad R. Lochmiller Michael A. Copland Ann Marie Tripps 《Mentoring & Tutoring: Partnership in Learning》2013,21(3):215-232
Administrators need intense support in their early years in their jobs to master the demands of the position and to emerge as effective leaders for their schools. This article reports on a leadership coaching program offered by a university to support graduates as they transition to new school leadership roles. First year research results of the Program for New Principals indicate that all of the program participants felt that the coaching program was a positive addition to the induction experience for new administrators. New principals viewed coaching positively and emphasized that it is both a valuable and unique form of professional development. Both coaches and new principals cited personalized support as one of the coaching model's most significant assets. The results should inform the development of a model of leadership coaching for new administrators. 相似文献
948.
A growing body of research documents the positive outcomes of research experiences for undergraduates, including increased persistence in science. Study of undergraduate lab learning experiences has demonstrated that the design of the experience influences the extent to which students report ownership of the project and that project ownership is one of the psychosocial factors involved in student retention in the sciences. To date, methods for measuring project ownership have not been suitable for the collection of larger data sets. The current study aims to rectify this by developing, presenting, and evaluating a new instrument for measuring project ownership. Eighteen scaled items were generated based on prior research and theory related to project ownership and combined with 30 items shown to measure respondents’ emotions about an experience, resulting in the Project Ownership survey (POS). The POS was analyzed to determine its dimensionality, reliability, and validity. The POS had a coefficient alpha of 0.92 and thus has high internal consistency. Known-groups validity was analyzed through the ability of the instrument to differentiate between students who studied in traditional versus research-based laboratory courses. The POS scales as differentiated between the groups and findings paralleled previous results in relation to the characteristics of project ownership. 相似文献
949.
Giles LV Warburton DE Esch BT Fedoruk MN Rupert JL Taunton JE 《Journal of sports sciences》2012,30(3):261-267
The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males. 相似文献
950.
Mohamed Saifeddin Fessi Nidhal Zarrouk Valter Di Salvo Cristoforo Filetti Alan R. Barker 《Journal of sports sciences》2016,34(24):2189-2194
ABSTRACTThis study aimed to examine: (i) the effect of decreasing training load (TL) during taper weeks on physical match activities in professional soccer players, and (ii) to disclose the relationship between weekly TL and physical match activities. Rating of perceived exertion was collected after each training session and match to quantify the TL in 19 professional players over 17 standard and 7 taper weeks during the season. Physical match activities were quantified by a computerised match analysis system and compared between standard training and taper weeks. Compared to standard weeks, the duration and frequency of training sessions during the taper weeks decreased (?21.7% and ?18.8%, respectively; P < 0.01) with no change in intensity (?4.8%; P = 0.09). Consequently, the weekly TL decreased during the taper weeks (?25.5%; P < 0.01). Increases in distance covered by intense running (+15.1%; P < 0.05), high-intensity running (HIR) (+15.7%; P < 0.01), number of sprints (+17.8%; P < 0.05) and number of high-speed runs (+15.7%; P < 0.05) were observed during the seven matches played after the taper weeks. High relationships were observed between TL and HIR distance covered, number of HIR and number of sprints (r = ?0.53; r = ?0.55; r = ?0.65, respectively; P < 0.01). Decreasing TL during taper weeks by reducing training duration and frequency but maintaining intensity was associated with an increase in physical activities during matches. However, it needs to be determined whether tapering or other match factors led to the changes in match activity. 相似文献