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861.
Probabilistic topic models are unsupervised generative models which model document content as a two-step generation process, that is, documents are observed as mixtures of latent concepts or topics, while topics are probability distributions over vocabulary words. Recently, a significant research effort has been invested into transferring the probabilistic topic modeling concept from monolingual to multilingual settings. Novel topic models have been designed to work with parallel and comparable texts. We define multilingual probabilistic topic modeling (MuPTM) and present the first full overview of the current research, methodology, advantages and limitations in MuPTM. As a representative example, we choose a natural extension of the omnipresent LDA model to multilingual settings called bilingual LDA (BiLDA). We provide a thorough overview of this representative multilingual model from its high-level modeling assumptions down to its mathematical foundations. We demonstrate how to use the data representation by means of output sets of (i) per-topic word distributions and (ii) per-document topic distributions coming from a multilingual probabilistic topic model in various real-life cross-lingual tasks involving different languages, without any external language pair dependent translation resource: (1) cross-lingual event-centered news clustering, (2) cross-lingual document classification, (3) cross-lingual semantic similarity, and (4) cross-lingual information retrieval. We also briefly review several other applications present in the relevant literature, and introduce and illustrate two related modeling concepts: topic smoothing and topic pruning. In summary, this article encompasses the current research in multilingual probabilistic topic modeling. By presenting a series of potential applications, we reveal the importance of the language-independent and language pair independent data representations by means of MuPTM. We provide clear directions for future research in the field by providing a systematic overview of how to link and transfer aspect knowledge across corpora written in different languages via the shared space of latent cross-lingual topics, that is, how to effectively employ learned per-topic word distributions and per-document topic distributions of any multilingual probabilistic topic model in various cross-lingual applications.  相似文献   
862.

This paper draws on an international study of the management challenges arising from diversifying academic and professional identities in higher education. These challenges include, for instance, the introduction of practice-based disciplines with different traditions such as health and social care, the changing aspirations and expectations of younger generations of staff, a diffusion of management responsibilities and structures, and imperatives for a more holistic approach to the “employment package”, including new forms of recognition and reward. It is suggested that while academic and professional identities have become increasingly dynamic and multi-faceted, change is occurring at different rates in different contexts. A model is offered, therefore, that relates approaches to “people management” to different organisational environments, against the general background of increasing resource constraint arising from the global economic downturn.

  相似文献   
863.
This work describes the genesis, articulation and consolidation from 2007 of a social network of b-learning (blended learning) in the UA (University of Alicante) (Spain), with the institutional backing of the Office of the Vice President for Education Technology and Innovation, and the momentum and advice of professor Angel Fidalgo (UNESCO (United Nations Educational, Scientific and Cultural Organization) chair for University of Management and Policy). The social network currently has more than 25 teachers, working on different work linkages with the university, implementing or intending to apply the teaching methodologyb-learning during the course 2007-2008 in a variety of courses and degrees. To do so, several resource centers (blogs, wikis, Wimba Create (before CourseGenie), etc.), and digital platforms (Virtual Campus of the UA, Moodle, etc.) are used.  相似文献   
864.
This study describes the development and validation of a Greek-language instrument that can be used to assess grade 10 students' perceptions of their chemistry classroom environment as a means of showing differences between chemistry learning environments in Greece (Attica) and Cyprus. The development of the instrument was based on available learning environment questionnaires. The questionnaire was administered to 1,394 students from 49 chemistry classes in Attica, and the resulting data were analyzed to explore the reliability and the validity of the new instrument. The validated questionnaire was administered to 225 students from 15 classes in urban areas of Cyprus. The data analyses supported the questionnaire's internal consistency, discriminant validity, and ability to differentiate between classrooms. Effect sizes and independent samples t test analyses revealed differences between the two samples. Cypriot students viewed their chemistry classroom environment more favorably than did the Attica students. A possible cause for this difference could be the knowledge-centered aspect of the grade 10 chemistry curriculum in Greece compared to the corresponding tool-instrumental knowledge curriculum in Cyprus.  相似文献   
865.
I reflect on studies by Rodriguez and Carlone, Haun-Frank, and Kimmel to emphasize the ways in which they excavate silences in the science education literature related to linguistic and cultural diversity and situating the problem of reform in teachers rather than contextual factors, such as traditional schooling discourses and forces that serve to marginalize science. I propose that the current push for top-down reform and accountability diminishes opportunities for receptivity, learning with and from students in order to transform teachers’ practices and promote equity in science education. I discuss tensions of agency and passivity in science education reform and argue that attention to authentic caring constitutes another silence in the science education literature. I conclude that the current policy context positions teachers and science education researchers as tempered radicals struggling against opp(reg)ressive reforms and that there is a need for more studies to excavate these and other silences.  相似文献   
866.
The nature of anatomy education has changed substantially in recent decades, though the traditional multiple‐choice written examination remains the cornerstone of assessing students' knowledge. This study sought to measure the quality of a clinical anatomy multiple‐choice final examination using item response theory (IRT) models. One hundred seventy‐six students took a multiple‐choice clinical anatomy examination. One‐ and two‐parameter IRT models (difficulty and discrimination parameters) were used to assess item quality. The two‐parameter IRT model demonstrated a wide range in item difficulty, with a median of ?1.0 and range from ?2.0 to 0.0 (25th to 75th percentile). Similar results were seen for discrimination (median 0.6; range 0.4–0.8). The test information curve achieved maximum discrimination for an ability level one standard deviation below the average. There were 15 items with standardized loading less than 0.3, which was due to several factors: two items had two correct responses, one was not well constructed, two were too easy, and the others revealed a lack of detailed knowledge by students. The test used in this study was more effective in discriminating students of lower ability than those of higher ability. Overall, the quality of the examination in clinical anatomy was confirmed by the IRT models. Anat Sci Educ 3:17–24, 2010. © 2009 American Association of Anatomists.  相似文献   
867.
The developmental trajectories of behavioral control and resiliency from early childhood to adolescence and their effects on early onset of substance use were examined. Behavioral control is the tendency to express or contain one's impulses and behaviors. Resiliency is the ability to adapt flexibly one's characteristic level of control in response to the environment. Study participants were 514 children of alcoholics and matched controls from a longitudinal community sample (Time 1 age in years: M =4.32, SD =0.89). Children with slower rates of increase in behavioral control were more likely to use alcohol and other drugs in adolescence. Children with higher initial levels of resiliency were less likely to begin using alcohol.  相似文献   
868.
OBJECTIVE: To develop and evaluate a web-based interactive information skills tutorial integrated into the curriculum. To determine whether the tutorial was acceptable to students and explore the use of a skills assessment tool in identifying whether the tutorial improved skills. METHODS: The development of a tutorial on OVID medline to teach transferable information skills. A small cohort study to evaluate students' views on the tutorial and its effects on information skills. RESULTS: Thirteen objective assessments were usable. There was a statistically significant improvement in mean final assessment scores, compared with mean pre-training scores, F(2,14) = 11.493, P = 0.001. Eleven (85%) students had improved their overall information skills. The improvement in overall searching skills was enhanced by referral to the tutorial. CONCLUSIONS: The tutorial was successfully developed and integrated into a Masters programme curriculum. In this setting, it appears to reinforce active learning, and was well received by students, who developed core generic searching skills and demonstrated improved information skills in the short and longer term. Students could use the tutorial for revision and study at a time and place of their choosing. Further evaluation is required to assess the impact of using the tutorial with large groups of students, and as a stand-alone teaching medium.  相似文献   
869.
The Republic of Venice was renowned for gathering and preserving from very early on a huge and growing archive. This article analyses the ways in which records were created, stored, and ordered for both immediate and future use. The political system of Venice, at once aristocratic and republican, had an important impact on the production and preservation of large quantities of documents in unbound filze and bound registri. In turn, the volume of this paperwork required the development of strict criteria for the organization of the material. In particular, this article analyses how records were divided at the moment of production, thus enabling a pragmatic combination of chronological and thematic ordering criteria. The latter were reinforced by finding tools arranged by subject matter, in particular indexes inside each volume and more general indexes across several volumes, both known as rubriche. The article suggests that indexing must be seen as a historical process dependent on Venice’s political structures and tied to specific moments in the wider history of the Republic, respectively in the fifteenth, early sixteenth, and early seventeenth centuries. Finally, the article points to some unexpected interactions between political secrecy and indexing.  相似文献   
870.
What hampers innovation? Revealed barriers versus deterring barriers   总被引:1,自引:0,他引:1  
Innovating firms are likely to face several challenges and experience different types of barriers. In this paper we argue that it is necessary to distinguish between two kinds of barriers to innovation. The first corresponds to what we describe as revealed barriers and reflects the degree of difficulty of the innovation process and the learning experience consequent on the firm engaging in innovation activity. The second type of impediment, which we label deterring barriers, encompasses the obstacles that prevent firms from committing to innovation. We use data from the 4th UK Community Innovation Survey (CIS4) to investigate the relationship between firms’ engagement in innovation and their assessment of the barriers to innovation. We show that the relationship is curvilinear in the case of costs and market barriers. These results have important implications for innovation policy and innovation management.  相似文献   
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