1,721,001 research outputs found
Use Context Information to Improve the Performance of Latent Dirichlet Allocation
No full text隱含狄利克雷分布模型是一種常被用來尋找文件中隱含主題的主題
模型，在一些情況之下，例如︰文件數目不足的文本或者是須要前後
文才能判斷意思的字，傳統的隱含狄利克雷分布模型會得到比較差的
結果。造成這個問題的主因是因為一個字可以包含有多種意思，不看
前後文的情況之下，很難分辨一個字真正的意思。在一些之前的研究
中，他們打破原本隱含狄利克雷分布模型中對於字是彼此獨立的假設
並嘗試著把字與字之間的關係加進他們所提的主題模型。在這篇研究
中，我們提出了一個新的模型－包含前後文隱含狄利克雷分布模型。
首先，我們的模型會將原本的文本轉成一堆帶有前後文資訊的「意義向量」，並找出這些向量彼此之間的等價關係；接著我們主題模型會在這些向量與他們之間的等價關係中找出原本文件隱含主題。包含前後文隱含狄利克雷分布模型不僅可以解決傳統的隱含狄利克雷分布模型所遇到的問題，還可以簡單的被平行及擴充。就算文本的數目不足，只要額外給予一些字與字之間的關係包含前後文隱含狄利克雷分布模型仍然可以得到不錯的結果。我們在20Newsgroup 這個文本上做了許多不同的實驗來驗證我們模型的效能，這些實驗數據顯示了我們模型的效能的確比隱原本的狄利克雷分布模型要來的好。最後，我們也列出了兩個模型在同一個文本中找出來的隱含主題。Latent Dirichlet Allocation (LDA), is a wildly used topic model for discovering the topics in documents, however it suffers from many problems like lack of dependency between words and sparse data. The main cause of these problems is the word-sense disambiguation in the natural language. In previous works, they ignore the assumption of "bag of words" and add the dependency between each words. However, we use different approach. In order to solve these problems, we proposed a topic model called context LDA (CLDA) model.
The CLDA model first build up concept vectors with context information at each position and use these vectors to distinguish the equivalent relationships between word, then we present a topic model which can take these relationship as input and model the words into latent topics. The CLDA model can not only overcome the word disambiguation problem but also be easily parallelized and extended. With some extra knowledge and slight modification, we show that our model can solve the sparse data problem easily. We conduct several experiments based on 20Newsgroup dataset; in the results we show that our model can actually improve the performance of the original LDA and fix the imbalance topic problem via using the vectors and equivalent relationships. Finally we show the examples of latent topics produced by the LDA model and our model.Contents
致謝i
中文摘要ii
Abstract iii
Contents iv
List of Figures vi
List of Tables vii
1 Introduction 1
2 Related Work 3
2.1 Latent Dirichlet Allocation . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Previous work on disambiguation problem . . . . . . . . . . . . . . . . . 5
3 Our proposed method 8
3.1 Concept vector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.1 Kernel function . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.2 Equivalent between vectors . . . . . . . . . . . . . . . . . . . . 12
3.2 Context LDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4 Inference of Gibbs Sampling 16
4.1 Inference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.2 Algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.3 Complexity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5 Extension 24
6 Experiment 26
6.1 Dataset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.2 Parameter measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
6.3 Information rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.4 Clustering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
6.5 Document Classification . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6.6 Word example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7 Conclusions and Future work 35
Bibliography 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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
- …
