1,721,043 research outputs found
Robust principal component analysis based on modified minimum Covariance determinant in the presence of outliers
No full textKlasik temel bileşenler analizi (KTBA), çok değişkenli veri kümelerinde yer alabilen aykırı gözlemlere karşı dayanıklı değildir. Aykırı gözlemlerin varlığında KTBA kullanılarak elde edilen sonuçlar gerçekte olması gerekenden oldukça farklı çıkabilir. Bu yüzden, aykırı gözlemlerin varlığında PCA'nın dayanıklı versiyonlarının kullanımı tercih edilmelidir. Dayanıklı temel bileşenleri elde etmek için en kolay yol konum ve ölçek parametrelerinin klasik tahminleriyle, onların dayanıklı tahminlerinin yer değiştirilmesidir. Çok değişkenli veri kümesi için konum ve ölçek parametrelerinin dayanıklı tahmini, yüksek bozulma noktası sağlayan en küçük kovaryans determinant (EKKD) yöntemi ile yapılabilir. Bu çalışmada, EKKD yöntemi, jackknife yeniden örnekleme yaklaşımı kullanılarak uyarlanıp, bu uyarlamadan kaynaklanan değişimlerin dayanıklı temel bileşenler analizi (DTBA) üzerindeki etkilerin incelenmesi amaçlanmaktadır. Jackknife yeniden örnekleme yöntemine dayanan EKKD'nin aykırı gözlem oranındaki değişmelerden nasıl etkilendiği iki gerçek veri kümesi için değerlendirilmektedir. Elde edilen bulgular ışığında, önerilen uyarlanmış en küçük kovaryans determinant (UEKKD) tahminine dayalı DTBA, klasik EKKD'ye dayanan DTBA'ya göre veri kümesinde aykırı gözlemlerin varlığında daha iyi sonuçlar verdiği görülmektedir.Principal component analysis (PCA) is not resistant to outliers existing in multivariate data sets. The results which are obtained by using classical PCA are far from real values in the presence of outliers. Therefore, using robust versions of PCA is favorable. The easiest way to obtain robust principal components is to replace classical estimates of the location and scale parameters with their robust versions. Robust estimations of location and scale parameters can be found with minimum covariance determinant (MCD) providing high breakdown point. In this study, algorithm of MCD is modified using Jackknife resampling approach and results of this modification are examined. Proposed robust principal component analysis (RPCA) based on modified MCD (MMCD) method that is modified using Jaccknife resampling are evaluated over two real data with different outlier ratios. In the light of obtained results, it can be said that RPCA based on MMCD is better than RPCA based on MCD in the presence of outliers
Turkish literature as world literature
No full textEssays covering a broad range of genres and ranging from the late Ottoman era to contemporary literature open the debate on the place of Turkish literature in the globalized literary world. Explorations of the multilingual cosmopolitanism of the Ottoman literary scene are complemented by examples of cross-generational intertextual encounters. The renowned poet Nâzim Hikmet is studied from a variety of angles, while contemporary and popular writers such as Orhan Pamuk and Elif Safak are contextualized. Turkish Literature as World Literature not only fills a significant lacuna in world literary studies but also draws a composite historical, political, and cultural portrait of Turkey in its relations with the broader world
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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