Saarbrücken, Universiẗat, Diss., 2002.

Thesis (Ph. D.)--University of Oklahoma, 1995. / Includes bibliographical references (leaves 79-86).

Project report (M.I.S.)--Virginia Polytechnic Institute and State University. / Abstract. Includes bibliographical references (leaves 44-45). Also available via the Internet.

Consumer's opinions and sentiments on products can reflect the performance of products in general or in various aspects. Analyzing these data is becoming feasible, considering the availability of immense data and the power of natural language processing. However, retailers have not taken full advantage of online comments. This work is dedicated to a solution for automatically analyzing and summarizing these valuable data at both product and category levels. In this research, a system was developed to retrieve and analyze extensive data from public online resources. A parallel framework was created to make this system extensible and efficient. In this framework, a star topological network was adopted in which each computing unit was assigned to retrieve a fraction of data and to assess sentiment. Finally, the preprocessed data were collected and summarized by the central machine which generates the final result that can be rendered through a web interface. The system was designed to have sound performance, robustness, manageability, extensibility, and accuracy.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Der große Vorteil eines q-Gramm Indexes liegt darin, dass es möglich ist beliebige Zeichenketten in einer Dokumentensammlung zu suchen. Ein Nachteil jedoch liegt darin, dass bei größer werdenden Datenmengen dieser Index dazu neigt, sehr groß zu werden, was mit einem deutlichem Leistungsabfall verbunden ist. In dieser Arbeit wird eine neuartige Technik vorgestellt, die die Leistung eines q-Gramm Indexes mithilfe zusätzlicher M-Matrizen für jedes q-Gramm und durch die Kombination mit einem invertierten Index erhöht. Eine M-Matrix ist eine Bit-Matrix, die Informationen über die Positionen eines q-Gramms enthält. Auch bei der Kombination von zwei oder mehreren Q-Grammen bieten diese M-Matrizen Informationen über die Positionen der Kombination. Dies kann verwendet werden, um die Komplexität der Zusammenführung der q-Gramm Trefferlisten für eine gegebene Suchanfrage zu reduzieren und verbessert die Leistung des n-Gramm-invertierten Index. Die Kombination mit einem termbasierten invertierten Index beschleunigt die durchschnittliche Suchzeit zusätzlich und vereint die Vorteile beider Index-Formate. Redundante Informationen werden in dem q-Gramm Index reduziert und weitere Funktionalität hinzugefügt, wie z.B. die Bewertung von Treffern nach Relevanz, die Möglichkeit, nach Konzepten zu suchen oder Indexpartitionierungen nach Wichtigkeit der enthaltenen Terme zu erstellen. / The major advantage of the n-gram inverted index is the possibility to locate any given substring in a document collection. Nevertheless, the n-gram inverted index also has its drawbacks: If the collections are getting bigger, this index tends to be very large and the performance drops significantly. A novel technique is proposed to enhance the performance of an n-gram inverted index by using additional m-matrixes for each n-gram and by combining it with an inverted index. An m-matrix is a bit matrix containing information about the positions of an n-gram. When combining two or more n-grams, these m-matrixes provide information about the positions of the combination. This can be used to reduce the complexity of merging the n-gram postings lists for a given search and improves the performance of the n-gram inverted index. The combination with a term based inverted index speeds up the average search time even more and combines the benefits of both index formats. Redundant information is reduced in the n-gram index and further functionality is added like the ranking of hits, the possibility to search for concepts and to create index partitions according to the relevance of the contained terms.

Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Lois Wright Hawkes, Florida State University, College of Arts and Sciences, Dept. of Computer Science. Title and description from dissertation home page (viewed Sept. 25, 2003). Includes bibliographical references.

Zugl.: Aachen, Techn. Hochsch., Diss., 2007

Chemnitz, Techn. Univ., Diplomarb., 2008.

Thesis (Ph. D.)--Drexel University, 2005. / Includes abstract and vita. Includes bibliographical references (leaves 171-190).