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Regression approaches for multi-class cost-sensitive classification
No full text成本導向多重分類問題在近年來越來越為重要，在圖形辨識和醫學究等問題上有很高的應用價值。為了使做出的分類決策可以達到最成本，陸續有許多研究者提出了加入成本資訊的機器學習演算法。些演算法中最常見的步驟，是將成本資訊轉化為每筆資料的比重。本篇論文中，我們採取了一項不同的步驟：利用迴歸分析來預估每資料相對應的分類成本，並依最低的預估成本來做分類決策。此方簡單並可以和各式的迴歸分析演算法結合，並有很強的理論基礎支。我們更進一步的分析了前述方法的盲點，利用創新的迴歸損失函，配合支持向量機，來設計更強而有力的成本導向多重分類演算，並透過實驗展示了本演算法的優越性。Cost-sensitive classification is an important research problem in recentears. It allows machine learning algorithms to use the additional cost informationo make more strategic decisions.tudies on binary cost-sensitive classification have led to promising resultsn theories, algorithms, and applications. The multi-class counterpart islso needed in many real-world applications, but is more difficult to analyze.his thesis focuses on multi-class cost-sensitive classification.xisting methods for multi-class cost-sensitive classification usually transformhe cost information into example importance (weight). This thesis offers different viewpoint of the problem, and proposes a novel method. Weirectly estimate the cost value corresponding to each prediction using regression,nd outputs the label that comes with the smallest estimated cost.e improve the method by analyzing the errors made during the decision.hen, we propose a different regression loss function that tightly connectsith the errors. The new loss function leads to a solid theoretical guaranteef error transformation. We design a concrete algorithm for the loss functionith the support vector machines. The algorithm can be viewed as a theoreticallyustified extension the popular one-versus-all support vector machine.xperiments using real-world data sets with arbitrary cost values demonstratehe usefulness of our proposed methods, and validate that the cost informationhould be appropriately used instead of dropped.致謝i文摘要iiibstract v Introduction 1.1 Problem Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Existing Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Contribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Cost-Sensitive Classification by Per Class Regression 9.1 Regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.3 Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.4 Regression Error Bound . . . . . . . . . . . . . . . . . . . . . . . . . . 11.5 Experimental Result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Cost-Sensitive Classification by One-Sided Regression 19.1 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19.2 One-sided Support Vector Regression . . . . . . . . . . . . . . . . . . . 24.2.1 Experiment Result . . . . . . . . . . . . . . . . . . . . . . . . . 26.2.2 Comparison with Artificial Data Set . . . . . . . . . . . . . . . . 27.2.3 Comparison with Benchmark Data Sets . . . . . . . . . . . . . . 28 Conclusion 31ibliography 3
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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