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Sparse probability density function estimation using the minimum integrated square error
No full textWe develop a new sparse kernel density estimator using a forward constrained regression framework, within which the nonnegative and summing-to-unity constraints of the mixing weights can easily be satisfied. Our main contribution is to derive a recursive algorithm to select significant kernels one at time based on the minimum integrated square error (MISE) criterion for both the selection of kernels and the estimation of mixing weights. The proposed approach is simple to implement and the associated computational cost is very low. Specifically, the complexity of our algorithm is in the order of the number of training data N, which is much lower than the order of N2 offered by the best existing sparse kernel density estimators. Numerical examples are employed to demonstrate that the proposed approach is effective in constructing sparse kernel density estimators with comparable accuracy to those of the classical Parzen window estimate and other existing sparse kernel density estimators
Wavelet entropy based probabilistic neural network for classification
No full textRecently, wavelet transform (WT) has been enormously effectual in various scientific fields. As a matter of fact, WT has overcome the FFT in the difficult nature data tackling. A wavelet entropy based probabilistic neural network (PNN) for classification applications is proposed. Specifically, wavelet transform is performed on the original input feature data, and the entropy values of the wavelet decomposition signals are then extracted to use as the input to the PNN classifier. Two benchmark data sets, Breast Cancer and Diabetes, are used to demonstrate the efficiency of our proposed wavelet entropy based PNN (WEPNN) classifier. The test classification rates of 80.3% and 77.0% are achieved respectively for the two data sets using the WEPNN with Shannon entropy. Other published methods are used for comparison. The method is promising. For results accuracy enhancement, large data set might be utilized in the future work
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A radial basis function network classifier to maximise leave-one-output mutual information
No full textWe develop an orthogonal forward selection (OFS) approach to construct radial basis function (RBF) network classifiers for two-class problems. Our approach integrates several concepts in probabilistic modelling, including cross validation, mutual information and Bayesian hyperparameter fitting. At each stage of the OFS procedure, one model term is selected by maximising the leave-one-out mutual information (LOOMI) between the classifier’s predicted class labels and the true class labels. We derive the formula of LOOMI within the OFS framework so that the LOOMI can be evaluated efficiently for model term selection. Furthermore, a Bayesian procedure of hyperparameter fitting is also integrated into the each stage of the OFS to infer the l2-norm based local regularisation parameter from the data. Since each forward stage is effectively fitting of a one-variable model, this task is very fast. The classifier construction procedure is automatically terminated without the need of using additional stopping criterion to yield very sparse RBF classifiers with excellent classification generalisation performance, which is particular useful for the noisy data sets with highly overlapping class distribution. A number of benchmark examples are employed to demonstrate the effectiveness of our proposed approach
Automatische phonetische Transkription des Standard-Arabischen mit Anwendungen im NLP-Bereich
Get PDFPhonetic transcription is the transition from a written text to linguistic units. These units can be phonemes, allophones, syllables, allosyllables, or diphones depending on the field of application. In this thesis, the problem of automatic phonetic transcription
of Standard Arabic (SA) text is addressed. A rule-based approach, depending on a set of language-based well-defined transcription rules and a dictionary of exceptions,has been adopted in this work. Three applications based on this have been provided.
The contributions of this work can be summarized as follows:
1) Developing a reliable software package for automatic phonetic transcription of Standard Arabic (SA) text with an accuracy of higher than 99%.
2) Accomplishing the first comprehensive automatic statistical study of linguistic units at the level of SA as a whole; the results
of this study were utilized in the expanded version of the developed software package to include the automatic preparation of text corpora with the desired linguistic content.
3) Developing a robust program to identify classical Arabic poems meters depending on the reliable results of automatic phonetic transcription. The outcome of this work can be utilized in SA text-to-speech (TTS), computer-aided pronunciation learning (CAPL), and automatic speech recognition (ASR) systems.Phonetische Transkription ist der Übergang von einem geschriebenen Text zu sprachlichen Einheiten. Diese Einheiten können Phoneme, Allophone, Silben, Allosilben oder Diphone sein, abhängig von dem Anwendungsgebiet. Diese Arbeit beschäftigt sich mit dem Problem der automatischen phonetischen Transkription von standardarabischen (SA) Texten. Ein regelbasierter Ansatz, der von einer Reihe sprachbasierter
wohldefinierter Transkriptionsregeln und einem Lexikon von Ausnahmen abhängt,wurde in dieser Arbeit übernommen. Drei darauf basierende Anwendungen wurden zur Verfügung gestellt. Die Beiträge dieser Arbeit können wie folgt zusammengefasst werden:
1) Entwicklung eines zuverlässigen Softwarepakets für die automatische phonetische Transkription von SA-Text mit einer Genauigkeit von höher als 99%.
2) Durchführung der ersten umfassenden automatischen statistischen Studie von Spracheinheiten auf der Ebene des SA als Ganzes. Die Ergebnisse dieser Studie wurden in der Erweiterungsversion des entwickelten Softwarepakets verwendet, um die automatische Erstellung von Textkorpora mit dem gewünschten linguistischen Inhalt zu erlauben.
3) Die Entwicklung eines robusten Programms, um klassische arabische Versmasse zu identifizieren, abhängig von den zuverlässigen Ergebnissen der automatischen phonetischen Transkription. Die Ergebnisse dieser Arbeit können in Sprachsynthese für SA (TTS), computergestütztes Aussprachelernen (CAPL) und automatischer Spracherkennung (ASR) verwendet werden
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
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