1,720,959 research outputs found
O-D Matrix Estimation and Incident Detection in Urban Areas Using Artificial Neural Networks
No full textThe paper discusses the application of Neural Networks to OD estimation and assignment problems. Error Back Propagation Neural Networks, when suitably constrained to respect the road network structure, show an interesting formal analogy with both these problems. It is expected that the constrained neural network, because of its own structure, would be able to reproduce feasible states of the road network that are different to those learned from the observed sample. Following this analogy, a procedure is presented to detect both the occurrence and the extent of incidents in urban road networks. The procedure is then tested, as well as assignement and OD estimation problems, in a first experiment that confirms the goodness of this approach
Robust asset allocation strategies: relaxed versus classical robustness
No full textMany optimization problems involve parameters which are not known in advance, but can only be forecast or estimated. Such
problems fit perfectly into the framework of Robust Optimization that, given optimization problems with uncertain parameters, looks
for solutions that will achieve good objective function values for the realization of these parameters in given uncertainty sets.
Aim of this paper is to investigate and compare alternative forms of robustness in the context of portfolio asset allocation.
Starting with a relaxed form of robustness, which allows one to specify not only the values of the uncertainty parameters, but also their degree of feasibility, in the first part of the paper we propose a family of relaxed robust models, called norm-portfolio models, which use general norms to relax the classical notion of robustness.
Then, in the second part we test some norm-portfolio models, as well as various robust strategies from the literature, with real market data on different data sets.
To the best of our knowledge, this is the first attempt at comparing robust strategies of different kinds in the framework of portfolio asset allocation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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