Swapping documents and terms     

Charles L. A. Clarke  Gordon V. Cormack  Thomas R. Lynam  Chris Buckley  Donna Harman 《Information Retrieval》2009,12(6):680-694

Experiments were conducted to explore the impact of combining various components of eight leading information retrieval systems. Each system demonstrated improved effectiveness through the use of blind feedback, also known as pseudo-relevance feedback, a form of query expansion. Blind feedback uses the results of a preliminary retrieval step to augment the efficacy of a secondary retrieval step. The hybrid combination of primary and secondary retrieval steps from different systems in a number of cases yielded better effectiveness than either of the constituent systems alone. This positive combining effect was observed when entire documents were passed between the two retrieval steps, but not when only the expansion terms were passed. Several combinations of primary and secondary retrieval steps were fused using the CombMNZ algorithm; all yielded significant effectiveness improvement over the individual systems, with the best yielding an improvement of 13% (p = 10⁻⁶) over the best individual system and an improvement of 4% (p = 10⁻⁵) over a simple fusion of the eight systems.  相似文献   

Transparency and social responsibility issues for Wikipedia     

Adele Santana  Donna J. Wood 《Ethics and Information Technology》2009,11(2):133-144

Wikipedia is known as a free online encyclopedia. Wikipedia uses largely transparent writing and editing processes, which aim at providing the user with quality information through a democratic collaborative system. However, one aspect of these processes is not transparent—the identity of contributors, editors, and administrators. We argue that this particular lack of transparency jeopardizes the validity of the information being produced by Wikipedia. We analyze the social and ethical consequences of this lack of transparency in Wikipedia for all users, but especially students; we assess the corporate social performance issues involved, and we propose courses of action to compensate for the potential problems. We show that Wikipedia has the appearance, but not the reality, of responsible, transparent information production. This paper’s authors are the same as those who authored Wood, D. J. and Queiroz, A. 2008. Information versus. knowledge: Transparency and social responsibility issues for Wikipedia. In Antonino Vaccaro, Hugo Horta, and Peter Madsen (Eds.), Transparency, Information, and Communication Technology (pp. 261–283). Charlottesville, VA: Philosophy Documentation Center. Adele has changed her surname from Queiroz to Santana  相似文献   

Judging addicts: drug courts and coercion in the justice system     

Ojmarrh Mitchell 《Journal of Criminal Justice Education》2018,29(2):310-313

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Student trust in teachers and student perceptions of safety: positive predictors of student identification with school     

Roxanne M. Mitchell  Lisa Kensler  Megan Tschannen-Moran 《International Journal of Leadership in Education》2018,21(2):135-154

This study examined the effects of student trust in teacher and student perceptions of safety on identification with school. Data were collected from one large urban district in an eastern state. Participants included 5441 students in 3rd through 12th grades from 49 schools. Students responded to surveys that assessed student trust in teachers, safety and identification with school. Free and Reduced Lunch (a proxy for SES), school level and ethnicity were included as control variables. Two hypotheses guided the study. Hypothesis 1 stated that student trust, safety and identification with school would positively covary. Hypothesis 2 predicted that student trust in teachers and perceptions of safety were school properties that would individually and collectively explain differences among schools in student identification with school. Both hypotheses were confirmed. The results of the hierarchical linear model indicated that student trust in teachers and school safety accounted for 98% of the 22% of variance that exists among schools in student identification. SES, school level and ethnicity were not significant predictors of identification with school. Findings suggest that student trust in teachers and perceptions of safety may significantly contribute to student identification above the effects of SES, ethnicity and school level.  相似文献   

Education and Skills Development in China-Africa Cooperation     

Michael Mitchell Omoruyi EHIZUELEN 《Frontiers of Education in China》2018,13(4):553-600

Education, skills, and the development of an African workforce are at a critical moment. While it is recognized that Chinese firms hire local people, the focus of the debate is more on the position and opportunities for training and advancement. As such, the paper tries to answer the following questions. Does China really contribute to skills development in Africa? Does China employment, education, and skills transfer pattern contribute to Africa’s own structural transformation and benefit African workforce? In attempting to answer these questions, this paper first lays out the current magnitude of demand for skills in Africa and the priorities for education and skills transfer that can successfully address Africa’s skills shortage. Significantly, this will enable researchers and non-researchers to understand the diversity of Chinese firms’ skills transfer patterns and the reasons behind these patterns. In order to present a comprehensive and precise picture as well as understand the context for China and Africa education and skills transfer development, the paper draws from various data collected from diverse sources, including government statistics, firm reports, second-hand academic literature, local and international news media, official government reports, and research studies. The paper suggests that the assessment of skills transfer pattern should not only consider employees’ and employers’ direct interests, but also in the short run, skills transfer should focus on offering short, practical courses to secondary and higher education graduates involving primarily on-the-job training. In the long run, there is a need to change the way employees and students are trained, including curriculum reforms that favor science, technology, engineering, and mathematics. Emphasis should also be placed on critical thinking, problem-solving, discovery, and experiential training.  相似文献   

A theory of grand innovation prizes     

Alberto Galasso  Matthew Mitchell  Gabor Virag 《Research Policy》2018,47(2):343-362

The past decade has witnessed a resurgence in innovation awards, in particular of grand innovation prizes (GIPs) which are rewards to innovators developing technologies reaching performance goals and requiring breakthrough solutions. GIPs typically do not preclude the winner also obtaining patent rights. This is in stark contrast with mainstream economics of innovation theories where prizes and patents are substitute ways to generate revenue and encourage innovation. Building on the management of innovation literature which stresses the difficulty to specify ex-ante all the technical features of the winning technologies, we develop a model in which innovative effort is multi-dimensional and only a subset of innovation tasks can be measured and contracted upon. We show that in this environment patent rights and cash rewards are complements, and that GIPs are often preferable to patent races or prizes requiring technologies to be placed in the public domain. Moreover, our model uncovers a tendency for patent races to encourage speed of discovery over quality of innovation, which can be corrected by GIPs. We explore robustness to endogenous entry, costly public funds, and incomplete information by GIP organizers on the surplus created by the technology.  相似文献   

Reliability and validity of a modified 3-minute all-out swimming test in elite swimmers     

Lachlan J. G. Mitchell  David B. Pyne  Philo U. Saunders  Ben Rattray 《European Journal of Sport Science》2018,18(3):307-314

Critical speed (CS) testing is useful in monitoring training in swimmers, however, completing a series of time trials (TTs) regularly is time-consuming. The 3-minute test may be a solution with positive initial findings. This investigation examined whether a modified 3-minute test (12?×?25?m) could assess CS and supra-CS distance capacity (D’) in swimmers. A series of 12?×?25?m intervals were completed unpaced at maximal effort, interspersed with 5?s rest periods. The model speed?=?a e^{b t}?+?c was fitted to the data and integrated to calculate D’. The slowest two of the last four efforts were averaged to calculate CS. To assess reliability, 15 highly trained swimmers (9 females, 6 males) completed the 12?×?25?m twice within 72?h. Four measures were deemed reliable: peak velocity (0.01?m?s^?1; 0.5%, typical error and % coefficient of variation), CS (0.02?m?s^?1; 1.2%), D’ (1.22?m; 5.7%) and drop off % (0.70% points; 4.5%). To assess criterion validity, 21 swimmers (9 from reliability, 12 other) completed two competition races within 2 weeks of a 12?×?25?m in the same stroke. Traditional CS and D’ measures were calculated from competition performances (TT method). TT CS and 12?×?25?m CS were highly correlated (adj. R²?=?0.92, p?D’ values were moderately correlated (adj. R²?=?0.60, p?D’ accurately. The 12?×?25?m all-out swimming test is a reliable method for assessing CS and D’ in swimmers, however, the validity of D’ requires further investigation.  相似文献   

The case for a Benjamin Franklin Medal in Computer and Cognitive Science for Marvin L. Minsky     

Thomas T. Hewett  Mitchell Marcus 《Journal of The Franklin Institute》2002,339(3):295-302

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Cyber libraries: building the perfect beast     

Beales DI 《Medical reference services quarterly》2002,21(4):49-56

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Paradigm Shifts in and around Special Education in New Zealand     

David Mitchell 《Cambridge Journal of Education》2001,31(3):319-335

There are few sectors in New Zealand education that have been as frequently reviewed and subjected to such wide-ranging policy changes as special education. The evolution of special education policy that has taken place in the past decade reflects the coalescence of several paradigm shifts. Some of these have been in the field of special education, where there has been an international shift away from categorising students in terms of their disabilities to making judgements on their needs for educational support, and away from segregated educational provisions to more inclusive approaches. Others reflect changes in the broader education system, in particular the shift towards more local control of decision making about resource allocation. This paper will examine the tensions inherent in these paradigm shifts and the interactions between them.  相似文献