A comparison of extrinsic clustering evaluation metrics based on formal constraints     

Enrique Amigó  Julio Gonzalo  Javier Artiles  Felisa Verdejo 《Information Retrieval》2009,12(4):461-486

There is a wide set of evaluation metrics available to compare the quality of text clustering algorithms. In this article, we define a few intuitive formal constraints on such metrics which shed light on which aspects of the quality of a clustering are captured by different metric families. These formal constraints are validated in an experiment involving human assessments, and compared with other constraints proposed in the literature. Our analysis of a wide range of metrics shows that only BCubed satisfies all formal constraints. We also extend the analysis to the problem of overlapping clustering, where items can simultaneously belong to more than one cluster. As Bcubed cannot be directly applied to this task, we propose a modified version of Bcubed that avoids the problems found with other metrics.

Felisa VerdejoEmail:

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Key website factors in e-business strategy     

Blanca  Julio  M. Jos 《International Journal of Information Management》2009,29(5):362-371

The design of a quality website, as part of e-business strategy, has become a key element for success in the online market. This article analyzes the main factors that must be taken into account when designing a commercial website, concentrating on the Aceros de Hispania company and its business model. We have studied the features which determine website quality: accessibility, speed, navigability, content, and we have calculated the Web Assessment Index (WAI) proposed by Miranda and Bañegil [Miranda, F. J., & Bañegil, T. M. (2004). Quantitative evaluation of commercial websites: An empirical study of Spanish firms. International Journal of Information Management, 24(4), 313–328]. The results obtained provide several lessons which should be borne in mind when designing a commercial e-strategy. Firstly, it can be observed that Internet popularity and search engine positioning facilitate entry to practically inaccessible markets. Secondly, the navigability makes users feel comfortable and secure when browsing it, which increases the probability of a transaction being completed. Finally, the information provided on the website must be accurate, informative, updated and relevant to customers’ requirements. Like Aceros de Hispania, any company, thanks to the Internet, will be able to overcome the barriers which would impede its successful worldwide development in the offline market.  相似文献   

Interactive question answering: Is Cross-Language harder than monolingual searching?     

Fernando López-Ostenero  Víctor Peinado  Julio Gonzalo  Felisa Verdejo 《Information processing & management》2008

Is Cross-Language answer finding harder than Monolingual answer finding for users? In this paper we provide initial quantitative and qualitative evidence to answer this question.  相似文献   

THE EVOLUTION OF THE UNIVERSITY TEACHING STAFF IN SPAIN     

Julio R. Villanueva 《Higher Education in Europe》1985,10(2):19-27

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Disciplinary epistemologies,generic attributes and undergraduate academic writing in nursing and midwifery     

Julio Gimenez 《Higher Education》2012,63(4):401-419

Generic attributes such as ‘holding a critical stance’, ‘using evidence to support claims’, and ‘projecting an impersonal voice’ are central to disciplinary academic writing in higher education. These attributes, also referred to as ‘skills’, have for a long time been conceptualised as transferable in that once learnt students are able to use them in a variety of contexts and for a range of needs. Over the past few years, however, the conceptualisation of these attributes as transferable has come under close scrutiny as they have been identified to be highly context-sensitive rather than context-flexible as they were once thought to be. Drawing on data from a 2-year study on undergraduate academic writing in nursing and midwifery at a university in the UK, this paper critically examines the role of disciplinary epistemologies in the conceptualisation of these attributes in the two disciplines, and demonstrates how these beliefs help to shape academic writing at undergraduate level, thus contributing to debates on generic skills and attributes and specificity in disciplinary discourses. The paper concludes by highlighting the importance for writers to examine how knowledge is displayed, constructed and communicated in their disciplines, and the significance of analysing the relationship between disciplinary epistemologies, generic attributes and academic writing as a way of gaining access to and producing central discourses in their professional community.  相似文献   

ICT teacher training: a view of the TPACK model / Formación del profesorado en TIC: una visión del modelo TPACK     

Julio Cabero  Julio Barroso 《Cultura y Educación》2016,28(3):633-663

This paper presents a study on the TPACK model (Technological Pedagogical Content Knowledge), which focuses on the assumption that in order to use ICTs effectively in teaching, the instructor must be trained in technological, content and pedagogical knowledge. In consequence, education, teacher training and professional development programmes should provide learning opportunities so that teachers can develop and put into action the three areas included in the model. To analyse the TPACK model of the teachers included in the study, a translation of an already developed instrument was applied; its reliability resulted in a Cronbach’s alpha of .97. The sample was comprised of 1,368 people who conducted training activities related to education and technologies at universities in Spain, Argentina, Colombia, the Dominican Republic and Venezuela. The results reveal the need to stress not the technological aspects but the pedagogical and content knowledge, which is where the respondents earned the lowest scores.  相似文献   

Analysis of the distance covered by Brazilian professional futsal players during official matches     

Murilo José De Oliveira Bueno  Fabio Giuliano Caetano  Tiago Julio Costa Pereira  Nicolau Melo De Souza  Gustavo Damasceno Moreira  FáBIO Yuzo Nakamura 《Sports biomechanics / International Society of Biomechanics in Sports》2014,13(3):230-240

The purpose of this study was to measure and characterise the distances covered by Brazilian professional futsal players. The trajectories of 93 players during five matches were obtained using an automatic tracking method. The distances covered were analysed for different game conditions: over the entire game and during the times when the ball was out of play and in play separately. When the entire game was considered, the results showed that there was a reduction in the total distance covered per minute from the first [median ± IQR (interquartile range): 97.9 ± 16.2 m/min] to the second half (median = 90.3 m/min; IQR = 12.0), and when only the in-play time was considered (first half: 136.6 ± 17.2 m/min; second half: 129.2 ± 16.7 m/min). The percentage of distance covered in the standing and walking velocity range was higher in the second half than in the first when considering the entire game (30.8% and 28.0%, respectively) and during the in-play time (19.3% and 16.2%, respectively). In conclusion, this study verified that futsal players reduced the physical performance during the second half.  相似文献