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  • × theme_ss:"Automatisches Klassifizieren"
  1. AlQenaei, Z.M.; Monarchi, D.E.: ¬The use of learning techniques to analyze the results of a manual classification system (2016) 0.01 
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    Abstract
    Classification is the process of assigning objects to pre-defined classes based on observations or characteristics of those objects, and there are many approaches to performing this task. The overall objective of this study is to demonstrate the use of two learning techniques to analyze the results of a manual classification system. Our sample consisted of 1,026 documents, from the ACM Computing Classification System, classified by their authors as belonging to one of the groups of the classification system: "H.3 Information Storage and Retrieval." A singular value decomposition of the documents' weighted term-frequency matrix was used to represent each document in a 50-dimensional vector space. The analysis of the representation using both supervised (decision tree) and unsupervised (clustering) techniques suggests that two pairs of the ACM classes are closely related to each other in the vector space. Class 1 (Content Analysis and Indexing) is closely related to Class 3 (Information Search and Retrieval), and Class 4 (Systems and Software) is closely related to Class 5 (Online Information Services). Further analysis was performed to test the diffusion of the words in the two classes using both cosine and Euclidean distance.
    Type
    a
  2. Wang, H.; Hong, M.: Supervised Hebb rule based feature selection for text classification (2019) 0.01 
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    Abstract
    Text documents usually contain high dimensional non-discriminative (irrelevant and noisy) terms which lead to steep computational costs and poor learning performance of text classification. One of the effective solutions for this problem is feature selection which aims to identify discriminative terms from text data. This paper proposes a method termed "Hebb rule based feature selection (HRFS)". HRFS is based on supervised Hebb rule and assumes that terms and classes are neurons and select terms under the assumption that a term is discriminative if it keeps "exciting" the corresponding classes. This assumption can be explained as "a term is highly correlated with a class if it is able to keep "exciting" the class according to the original Hebb postulate. Six benchmarking datasets are used to compare HRFS with other seven feature selection methods. Experimental results indicate that HRFS is effective to achieve better performance than the compared methods. HRFS can identify discriminative terms in the view of synapse between neurons. Moreover, HRFS is also efficient because it can be described in the view of matrix operation to decrease complexity of feature selection.
    Type
    a
  3. Na, J.-C.; Sui, H.; Khoo, C.; Chan, S.; Zhou, Y.: Effectiveness of simple linguistic processing in automatic sentiment classification of product reviews (2004) 0.01 
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    Abstract
    This paper reports a study in automatic sentiment classification, i.e., automatically classifying documents as expressing positive or negative Sentiments/opinions. The study investigates the effectiveness of using SVM (Support Vector Machine) an various text features to classify product reviews into recommended (positive Sentiment) and not recommended (negative sentiment). Compared with traditional topical classification, it was hypothesized that syntactic and semantic processing of text would be more important for sentiment classification. In the first part of this study, several different approaches, unigrams (individual words), selected words (such as verb, adjective, and adverb), and words labelled with part-of-speech tags were investigated. A sample of 1,800 various product reviews was retrieved from Review Centre (www.reviewcentre.com) for the study. 1,200 reviews were used for training, and 600 for testing. Using SVM, the baseline unigram approach obtained an accuracy rate of around 76%. The use of selected words obtained a marginally better result of 77.33%. Error analysis suggests various approaches for improving classification accuracy: use of negation phrase, making inference from superficial words, and solving the problem of comments an parts. The second part of the study that is in progress investigates the use of negation phrase through simple linguistic processing to improve classification accuracy. This approach increased the accuracy rate up to 79.33%.
    Type
    a
  4. Automatic classification research at OCLC (2002) 0.01 
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    Date
    5. 5.2003 9:22:09
  5. Yao, H.; Etzkorn, L.H.; Virani, S.: Automated classification and retrieval of reusable software components (2008) 0.01 
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    Abstract
    The authors describe their research which improves software reuse by using an automated approach to semantically search for and retrieve reusable software components in large software component repositories and on the World Wide Web (WWW). Using automation and smart (semantic) techniques, their approach speeds up the search and retrieval of reusable software components, while retaining good accuracy, and therefore improves the affordability of software reuse. A program understanding of software components and natural language understanding of user queries was employed. Then the software component descriptions were compared by matching the resulting semantic representations of the user queries to the semantic representations of the software components to search for software components that best match the user queries. A proof of concept system was developed to test the authors' approach. The results of this proof of concept system were compared to human experts, and statistical analysis was performed on the collected experimental data. The results from these experiments demonstrate that this automated semantic-based approach for software reusable component classification and retrieval is successful when compared to the labor-intensive results from the experts, thus showing that this approach can significantly benefit software reuse classification and retrieval.
    Type
    a
  6. Billal, B.; Fonseca, A.; Sadat, F.; Lounis, H.: Semi-supervised learning and social media text analysis towards multi-labeling categorization (2017) 0.01 
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    Abstract
    In traditional text classification, classes are mutually exclusive, i.e. it is not possible to have one text or text fragment classified into more than one class. On the other hand, in multi-label classification an individual text may belong to several classes simultaneously. This type of classification is required by a large number of current applications such as big data classification, images and video annotation. Supervised learning is the most used type of machine learning in the classification task. It requires large quantities of labeled data and the intervention of a human tagger in the creation of the training sets. When the data sets become very large or heavily noisy, this operation can be tedious, prone to error and time consuming. In this case, semi-supervised learning, which requires only few labels, is a better choice. In this paper, we study and evaluate several methods to address the problem of multi-label classification using semi-supervised learning and data from social networks. First, we propose a linguistic pre-processing involving tokeni-sation, recognition of named entities and hashtag segmentation in order to decrease the noise in this type of massive and unstructured real data and then we perform a word sense disambiguation using WordNet. Second, several experiments related to multi-label classification and semi-supervised learning are carried out on these data sets and compared to each other. These evaluations compare the results of the approaches considered. This paper proposes a method for combining semi-supervised methods with a graph method for the extraction of subjects in social networks using a multi-label classification approach. Experiments show that the performance of the proposed model increases in 4 p.p. the precision of the classification when compared to a baseline.
    Type
    a
  7. HaCohen-Kerner, Y.; Beck, H.; Yehudai, E.; Rosenstein, M.; Mughaz, D.: Cuisine : classification using stylistic feature sets and/or name-based feature sets (2010) 0.01 
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    Abstract
    Document classification presents challenges due to the large number of features, their dependencies, and the large number of training documents. In this research, we investigated the use of six stylistic feature sets (including 42 features) and/or six name-based feature sets (including 234 features) for various combinations of the following classification tasks: ethnic groups of the authors and/or periods of time when the documents were written and/or places where the documents were written. The investigated corpus contains Jewish Law articles written in Hebrew-Aramaic, which present interesting problems for classification. Our system CUISINE (Classification UsIng Stylistic feature sets and/or NamE-based feature sets) achieves accuracy results between 90.71 to 98.99% for the seven classification experiments (ethnicity, time, place, ethnicity&time, ethnicity&place, time&place, ethnicity&time&place). For the first six tasks, the stylistic feature sets in general and the quantitative feature set in particular are enough for excellent classification results. In contrast, the name-based feature sets are rather poor for these tasks. However, for the most complex task (ethnicity&time&place), a hill-climbing model using all feature sets succeeds in significantly improving the classification results. Most of the stylistic features (34 of 42) are language-independent and domain-independent. These features might be useful to the community at large, at least for rather simple tasks.
    Type
    a
  8. Automatische Klassifikation und Extraktion in Documentum (2005) 0.01 
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    Source
    Information - Wissenschaft und Praxis. 56(2005) H.5/6, S.276
    Type
    a
  9. Reiner, U.: VZG-Projekt Colibri : Bewertung von automatisch DDC-klassifizierten Titeldatensätzen der Deutschen Nationalbibliothek (DNB) (2009) 0.01 
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    Abstract
    Das VZG-Projekt Colibri/DDC beschäftigt sich seit 2003 mit automatischen Verfahren zur Dewey-Dezimalklassifikation (Dewey Decimal Classification, kurz DDC). Ziel des Projektes ist eine einheitliche DDC-Erschließung von bibliografischen Titeldatensätzen und eine Unterstützung der DDC-Expert(inn)en und DDC-Laien, z. B. bei der Analyse und Synthese von DDC-Notationen und deren Qualitätskontrolle und der DDC-basierten Suche. Der vorliegende Bericht konzentriert sich auf die erste größere automatische DDC-Klassifizierung und erste automatische und intellektuelle Bewertung mit der Klassifizierungskomponente vc_dcl1. Grundlage hierfür waren die von der Deutschen Nationabibliothek (DNB) im November 2007 zur Verfügung gestellten 25.653 Titeldatensätze (12 Wochen-/Monatslieferungen) der Deutschen Nationalbibliografie der Reihen A, B und H. Nach Erläuterung der automatischen DDC-Klassifizierung und automatischen Bewertung in Kapitel 2 wird in Kapitel 3 auf den DNB-Bericht "Colibri_Auswertung_DDC_Endbericht_Sommer_2008" eingegangen. Es werden Sachverhalte geklärt und Fragen gestellt, deren Antworten die Weichen für den Verlauf der weiteren Klassifizierungstests stellen werden. Über das Kapitel 3 hinaus führende weitergehende Betrachtungen und Gedanken zur Fortführung der automatischen DDC-Klassifizierung werden in Kapitel 4 angestellt. Der Bericht dient dem vertieften Verständnis für die automatischen Verfahren.
  10. Borko, H.: Research in computer based classification systems (1985) 0.01 
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    Abstract
    The selection in this reader by R. M. Needham and K. Sparck Jones reports an early approach to automatic classification that was taken in England. The following selection reviews various approaches that were being pursued in the United States at about the same time. It then discusses a particular approach initiated in the early 1960s by Harold Borko, at that time Head of the Language Processing and Retrieval Research Staff at the System Development Corporation, Santa Monica, California and, since 1966, a member of the faculty at the Graduate School of Library and Information Science, University of California, Los Angeles. As was described earlier, there are two steps in automatic classification, the first being to identify pairs of terms that are similar by virtue of co-occurring as index terms in the same documents, and the second being to form equivalence classes of intersubstitutable terms. To compute similarities, Borko and his associates used a standard correlation formula; to derive classification categories, where Needham and Sparck Jones used clumping, the Borko team used the statistical technique of factor analysis. The fact that documents can be classified automatically, and in any number of ways, is worthy of passing notice. Worthy of serious attention would be a demonstra tion that a computer-based classification system was effective in the organization and retrieval of documents. One reason for the inclusion of the following selection in the reader is that it addresses the question of evaluation. To evaluate the effectiveness of their automatically derived classification, Borko and his team asked three questions. The first was Is the classification reliable? in other words, could the categories derived from one sample of texts be used to classify other texts? Reliability was assessed by a case-study comparison of the classes derived from three different samples of abstracts. The notso-surprising conclusion reached was that automatically derived classes were reliable only to the extent that the sample from which they were derived was representative of the total document collection. The second evaluation question asked whether the classification was reasonable, in the sense of adequately describing the content of the document collection. The answer was sought by comparing the automatically derived categories with categories in a related classification system that was manually constructed. Here the conclusion was that the automatic method yielded categories that fairly accurately reflected the major area of interest in the sample collection of texts; however, since there were only eleven such categories and they were quite broad, they could not be regarded as suitable for use in a university or any large general library. The third evaluation question asked whether automatic classification was accurate, in the sense of producing results similar to those obtainabie by human cIassifiers. When using human classification as a criterion, automatic classification was found to be 50 percent accurate.
    Source
    Theory of subject analysis: a sourcebook. Ed.: L.M. Chan, et al
    Type
    a
  11. Wätjen, H.-J.; Diekmann, B.; Möller, G.; Carstensen, K.-U.: Bericht zum DFG-Projekt: GERHARD : German Harvest Automated Retrieval and Directory (1998) 0.01 
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  12. Wätjen, H.-J.: Automatisches Sammeln, Klassifizieren und Indexieren von wissenschaftlich relevanten Informationsressourcen im deutschen World Wide Web : das DFG-Projekt GERHARD (1998) 0.01 
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  13. Groß, T.; Faden, M.: Automatische Indexierung elektronischer Dokumente an der Deutschen Zentralbibliothek für Wirtschaftswissenschaften : Bericht über die Jahrestagung der Internationalen Buchwissenschaftlichen Gesellschaft (2010) 0.01 
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    Bibliotheksdienst. 44(2010) H.12, S.1120-1135
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  14. Oberhauser, O.: Automatisches Klassifizieren : Entwicklungsstand - Methodik - Anwendungsbereiche (2005) 0.00 
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    Footnote
    Rez. in: VÖB-Mitteilungen 58(2005) H.3, S.102-104 (R.F. Müller); ZfBB 53(2006) H.5, S.282-283 (L. Svensson): "Das Sammeln und Verzeichnen elektronischer Ressourcen gehört in wissenschaftlichen Bibliotheken längst zum Alltag. Parallel dazu kündigt sich ein Paradigmenwechsel bei den Findmitteln an: Um einen effizienten und benutzerorientierten Zugang zu den gemischten Kollektionen bieten zu können, experimentieren einige bibliothekarische Diensteanbieter wie z. B. das hbz (http://suchen.hbz-nrw.de/dreilaender/), die Bibliothek der North Carolina State University (www.lib.ncsu.edu/) und demnächst vascoda (www.vascoda.de/) und der Librarians-Internet Index (www.lii.org/) zunehmend mit Suchmaschinentechnologie. Dabei wird angestrebt, nicht nur einen vollinvertierten Suchindex anzubieten, sondern auch das Browsing durch eine hierarchisch geordnete Klassifikation. Von den Daten in den deutschen Verbunddatenbanken ist jedoch nur ein kleiner Teil schon klassifikatorisch erschlossen. Fremddaten aus dem angloamerikanischen Bereich sind oft mit LCC und/oder DDC erschlossen, wobei die Library of Congress sich bei der DDCErschließung auf Titel, die hauptsächlich für die Public Libraries interessant sind, konzentriert. Die Deutsche Nationalbibliothek wird ab 2007 Printmedien und Hochschulschriften flächendeckend mit DDC erschließen. Es ist aber schon offensichtlich, dass v. a. im Bereich der elektronischen Publikationen die anfallenden Dokumentenmengen mit immer knapperen Personalressourcen nicht intellektuell erschlossen werden können, sondern dass neue Verfahren entwickelt werden müssen. Hier kommt Oberhausers Buch gerade richtig. Seit Anfang der 1990er Jahre sind mehrere Projekte zum Thema automatisches Klassifizieren durchgeführt worden. Wer sich in diese Thematik einarbeiten wollte oder sich für die Ergebnisse der größeren Projekte interessierte, konnte bislang auf keine Überblicksdarstellung zurückgreifen, sondern war auf eine Vielzahl von Einzeluntersuchungen sowie die Projektdokumentationen angewiesen. Oberhausers Darstellung, die auf einer Fülle von publizierter und grauer Literatur fußt, schließt diese Lücke. Das selbst gesetzte Ziel, einen guten Überblick über den momentanen Kenntnisstand und die Ergebnisse der einschlägigen Projekte verständlich zu vermitteln, erfüllt der Autor mit Bravour. Dabei ist anzumerken, dass er ein bibliothekarisches Grundwissen und mindestens grundlegende Kenntnisse über informationswissenschaftliche Grundbegriffe und Fragestellungen voraussetzt, wobei hier für den Einsteiger einige Hinweise auf einführende Darstellungen wünschenswert gewesen wären.
    Zum Inhalt Auf einen kurzen einleitenden Abschnitt folgt eine Einführung in die grundlegende Methodik des automatischen Klassifizierens. Oberhauser erklärt hier Begriffe wie Einfach- und Mehrfachklassifizierung, Klassen- und Dokumentzentrierung, und geht danach auf die hauptsächlichen Anwendungen der automatischen Klassifikation von Textdokumenten, maschinelle Lernverfahren und Techniken der Dimensionsreduktion bei der Indexierung ein. Zwei weitere Unterkapitel sind der Erstellung von Klassifikatoren und den Methoden für deren Auswertung gewidmet. Das Kapitel wird abgerundet von einer kurzen Auflistung einiger Softwareprodukte für automatisches Klassifizieren, die sowohl kommerzielle Software, als auch Projekte aus dem Open-Source-Bereich umfasst. Der Hauptteil des Buches ist den großen Projekten zur automatischen Erschließung von Webdokumenten gewidmet, die von OCLC (Scorpion) sowie an den Universitäten Lund (Nordic WAIS/WWW, DESIRE II), Wolverhampton (WWLib-TOS, WWLib-TNG, Old ACE, ACE) und Oldenburg (GERHARD, GERHARD II) durchgeführt worden sind. Der Autor beschreibt hier sehr detailliert - wobei der Detailliertheitsgrad unterschiedlich ist, je nachdem, was aus der Projektdokumentation geschlossen werden kann - die jeweilige Zielsetzung des Projektes, die verwendete Klassifikation, die methodische Vorgehensweise sowie die Evaluierungsmethoden und -ergebnisse. Sofern Querverweise zu anderen Projekten bestehen, werden auch diese besprochen. Der Verfasser geht hier sehr genau auf wichtige Aspekte wie Vokabularbildung, Textaufbereitung und Gewichtung ein, so dass der Leser eine gute Vorstellung von den Ansätzen und der möglichen Weiterentwicklung des Projektes bekommt. In einem weiteren Kapitel wird auf einige kleinere Projekte eingegangen, die dem für Bibliotheken besonders interessanten Thema des automatischen Klassifizierens von Büchern sowie den Bereichen Patentliteratur, Mediendokumentation und dem Einsatz bei Informationsdiensten gewidmet sind. Die Darstellung wird ergänzt von einem Literaturverzeichnis mit über 250 Titeln zu den konkreten Projekten sowie einem Abkürzungs- und einem Abbildungsverzeichnis. In der abschließenden Diskussion der beschriebenen Projekte wird einerseits auf die Bedeutung der einzelnen Projekte für den methodischen Fortschritt eingegangen, andererseits aber auch einiges an Kritik geäußert, v. a. bezüglich der mangelnden Auswertung der Projektergebnisse und des Fehlens an brauchbarer Dokumentation. So waren z. B. die Projektseiten des Projekts GERHARD (www.gerhard.de/) auf den Stand von 1998 eingefroren, zurzeit [11.07.06] sind sie überhaupt nicht mehr erreichbar. Mit einigem Erstaunen stellt Oberhauser auch fest, dass - abgesehen von der fast 15 Jahre alten Untersuchung von Larsen - »keine signifikanten Studien oder Anwendungen aus dem Bibliotheksbereich vorliegen« (S. 139). Wie der Autor aber selbst ergänzend ausführt, dürfte dies daran liegen, dass sich bibliografische Metadaten wegen des geringen Textumfangs sehr schlecht für automatische Klassifikation eignen, und dass - wie frühere Ergebnisse gezeigt haben - das übliche TF/IDF-Verfahren nicht für Katalogisate geeignet ist (ibd.).
  15. Schek, M.: Automatische Klassifizierung und Visualisierung im Archiv der Süddeutschen Zeitung (2005) 0.00 
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    Medienwirtschaft. 2(2005) H.1, S.20-24
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  16. Sparck Jones, K.: Automatic classification (1976) 0.00 
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    Classification in the 1970s: a second look. Rev. ed. Ed.: A. Maltby
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  17. Ardö, A.; Koch, T.: Automatic classification applied to full-text Internet documents in a robot-generated subject index (1999) 0.00 
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  18. Schiminovich, S.: Automatic classification and retrieval of documents by means of a bibliographic pattern discovery algorithm (1971) 0.00 
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  19. Fong, A.C.M.: Mining a Web citation database for document clustering (2002) 0.00 
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  20. Dang, E.K.F.; Luk, R.W.P.; Ho, K.S.; Chan, S.C.F.; Lee, D.L.: ¬A new measure of clustering effectiveness : algorithms and experimental studies (2008) 0.00 
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    Abstract
    We propose a new optimal clustering effectiveness measure, called CS1, based on a combination of clusters rather than selecting a single optimal cluster as in the traditional MK1 measure. For hierarchical clustering, we present an algorithm to compute CS1, defined by seeking the optimal combinations of disjoint clusters obtained by cutting the hierarchical structure at a certain similarity level. By reformulating the optimization to a 0-1 linear fractional programming problem, we demonstrate that an exact solution can be obtained by a linear time algorithm. We further discuss how our approach can be generalized to more general problems involving overlapping clusters, and we show how optimal estimates can be obtained by greedy algorithms.
    Type
    a

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