Multinomial logistic regression probability ratio-based feature vectors for Malay vowel recognition

Vowel Recognition is a part of automatic speech recognition (ASR) systems that classifies speech signals into groups of vowels. The performance of Malay vowel recognition (MVR) like any multiclass classification problem depends largely on Feature Vectors (FVs). FVs such as Mel-frequency Cepstral Coefficients (MFCC) have produced high error rates due to poor phoneme information. Classifier transformed probabilistic features have proved a better alternative in conveying phoneme information. However, the high dimensionality of the probabilistic features introduces additional complexity that deteriorates ASR performance. This study aims to improve MVR performance by proposing an algorithm that transforms MFCC FVs into a new set of features using Multinomial Logistic Regression (MLR) to reduce the dimensionality of the probabilistic features. This study was carried out in four phases which are pre-processing and feature extraction, best regression coefficients generation, feature transformation, and performance evaluation. The speech corpus consists of 1953 samples of five Malay vowels of /a/, /e/, /i/, /o/ and /u/ recorded from students of two public universities in Malaysia. Two sets of algorithms were developed which are DBRCs and FELT. DBRCs algorithm determines the best regression coefficients (DBRCs) to obtain the best set of regression coefficients (RCs) from the extracted 39-MFCC FVs through resampling and data swapping approach. FELT algorithm transforms 39-MFCC FVs using logistic transformation method into FELT FVs. Vowel recognition rates of FELT and 39-MFCC FVs were compared using four different classification techniques of Artificial Neural Network, MLR, Linear Discriminant Analysis, and k-Nearest Neighbour. Classification results showed that FELT FVs surpass the performance of 39-MFCC FVs in MVR. Depending on the classifiers used, the improved performance of 1.48% - 11.70% was attained by FELT over MFCC. Furthermore, FELT significantly improved the recognition accuracy of vowels /o/ and /u/ by 5.13% and 8.04% respectively. This study contributes two algorithms for determining the best set of RCs and generating FELT FVs from MFCC. The FELT FVs eliminate the need for dimensionality reduction with comparable performances. Furthermore, FELT FVs improved MVR for all the five vowels especially /o/ and /u/. The improved MVR performance will spur the development of Malay speech-based systems, especially for the Malaysian community

Variation and change in the vowel system of Tyneside English

PhD ThesisThis thesis presents a variationist account of phonological variation and change in the vowel system of Tyneside English. The distributions of the phonetic exponents of five vowel variables are assessed with respect to the social variables sex, age and social class. Using a corpus of conversational and word-list material, for which 32 speakers of Tyneside English were recorded, between 30 and 40 tokens per speaker of the variables (i), (u), (e), (o) and (3) were transcribed impressionistically and subclassified by following phonological context. The results of this analysis are significant on several counts. First, the speakers sampled appear to differentiate themselves within the speech community through the variable use of certain socially marked phonetic variants, which can be correlated with the sex, age and class variables. Secondly, the speakers style shift to a greater or lesser degree according to combinations of the three social factors, such that surface variability is reduced as a function of increased formality. Third, the overall pattern among the sample population seems to be one of increasing uniformity or convergence: it is speculated that social mobility among upper working- and lower-middle class groups may lead to accent levelling, whereby local speech forms are supplanted by supra-local or innovative intermediate ones. That is, the patterns observed here may be indicative of change in progress. Last, a comparison of the results for the (phonologically) paired variables (i u) and (e o) shows a strong tendency for Tyneside speakers to use these 'symmetrically', in that choice of variant in one variable predicts choice of variant in the other. It is suggested that the symmetry in the system is exploited by Tyneside speakers for the purposes of indicating social affiliation and identity, and is in this sense an extra sociolinguistic resource upon which speakers can draw. In addition, the variants of (3) are discussed with reference to the reported merger of this variable with (a); it is suggested that the apparent 'unmerging' of these two classes is unproblematic from a structural point of view, as the putative (3)—(o) merger appears never to have been completed.UK Economic and Social Research Council (award number R00429524350

De l'accentuation lexicale en anglais australien standard contemporain.

La littérature scientifique dédiée à l accentuation en anglais australien standard contemporain (SAusE) est, contrairement à celle qui concerne la prononciation de ses voyelles, peu étendue. Après un chapitre introductif proposant le contexte historique dans lequel le SAusE est né et a été décrit, sa définition actuelle ainsi que sa description phonologique, notre étude est consacrée à un examen systémique de l accentuation lexicale en SAusE. Un corpus test a été mis en place spécifiquement, qui comporte la quasi-totalité des verbes dissyllabiques, des préfixés pluricatégoriels et des exceptions aux règles d accentuation des mots de deux syllabes et plus, ainsi qu un large échantillon d emprunts aux langues aborigènes. Ces quelques 3500 items ont été choisis précisément parce qu ils font partie des mots les plus susceptibles de connaître une variation accentuelle en anglais contemporain. Notre approche se situe dans la lignée de Lionel Guierre et propose un traitement dictionnairique dans lequel les éléments du corpus sont tous étudiés au travers des données de chacune des éditions les plus récentes des Longman Pronouncing Dictionary, Cambridge English Pronunciation Dictionary et Macquarie Dictionary qui constituent les dictionnaires de références dans le domaine de la prononciation de l anglais. Ces données ont été complétées, lorsque cela était nécessaire, par des données fréquentielles issues du Corpus of Contemporary American English et par des données orales enregistrées spécialement pour cette étude, selon une démarche similaire à la première partie du protocole du projet Phonologie de l Anglais Contemporain. Notre analyse met en évidence une grande stabilité accentuelle intervariétale entre le SAusE, l anglais britannique standard et l anglais américain standard et propose un relevé étayé et détaillé des spécificités accentuelles lexicales du SAusE contenues dans le corpus étudié.The scientific literature dedicated to word stress in contemporary standard Australian English (SAusE) is not very extensive contrary to the one dealing with the pronunciation of vowels in this variety of English. We will introduce the historical context in which SAusE first emerged and was described, its current definition as well as its phonological description. Our study is then devoted to the systemic study of lexical word stress in SAusE. A corpus was specifically put together for this particular research : it includes most of the dissyllabic verbs, of the prefixed multicategorial words and of the words that are exceptions to the rules of word-stress assignment in English, as well as a large sample of borrowings from Aboriginal languages. These 3500 items were not chosen randomly : they are words which specifically tend to show word-stress variation in contemporary English. Our approach follows Lionel Guierre s and offers a dictionary treatment in which all the elements of our corpus are studied using the data of each of the most recent editions of the Longman Pronouncing Dictionary, the Cambridge English Pronunciation Dictionary and the Macquarie Dictionary, all reference books on English pronunciation. Frequency data extracted from the Corpus of Contemporary American English and oral data recorded for this study (following a protocol similar to that which is applied in the first part of the project Phonologie de l Anglais Contemporain) were added to the dictionary data when necessary. Our analysis brings to the fore a great accentual intervarietal stability between SAusE, standard British English and standard American English, and offers a detailed and complete list of the lexical accentual specificities of SAusE ascertained through our study.TOURS-Bibl.électronique (372610011) / SudocSudocFranceF

Accents on Trial: Accent Discrimination in U.K. and U.S. Courts

Research into urban housing, employment, education, and public perception has found evidence of accent discrimination. However, the role of language and discrimination has been under researched in the legal realm. Trials such as the U.S. Zimmerman v. State with witness Rachel Jeantel reveal how damaging accent discrimination can be. In order to research this further, mock trials were put together, collecting “verdicts” from groups of participants in the U.S. who formed mock juries, as well as individual online participants in the U.K. and the U.S. In both countries the national standard accent was compared to a regional accent. This was done by filming a staged cross examination between a prosecutor and a defendant. While the prosecutor’s accent remained standard in both guises, participants were given a video that had the defendant testify in either a standard or regional accent. Unlike previous research, these studies were designed to look like psychological studies into jury decision making so that participants were not primed for the linguistic components. The statistical analysis did not find any significant differences between the two accent conditions. Therefore, while language attitudes affected some of the results, there was no evidence that accent discrimination was present when it came to giving a verdict. Thus the overall findings suggest accent may not always be discriminated against directly; rather it may be the vehicle used to discriminate against protected traits (e.g. ethnicity, gender, religion, etc.). Furthermore, the mock juries differed significantly in their verdicts from the individual online participants. This suggests that the use of individual jurors in any type of trial research significantly inhibits ecological validity. Suggestions for further research are offered to continue learning in what ways language is instrumental in legal contexts

Models and analysis of vocal emissions for biomedical applications

This book of Proceedings collects the papers presented at the 3rd International Workshop on Models and Analysis of Vocal Emissions for Biomedical Applications, MAVEBA 2003, held 10-12 December 2003, Firenze, Italy. The workshop is organised every two years, and aims to stimulate contacts between specialists active in research and industrial developments, in the area of voice analysis for biomedical applications. The scope of the Workshop includes all aspects of voice modelling and analysis, ranging from fundamental research to all kinds of biomedical applications and related established and advanced technologies

Making accurate formant measurements: an empirical investigation of the influence of the measurement tool, analysis settings and speaker on formant measurements

The aim of this thesis is to provide guidance and information that will assist forensic speech scientists, and phoneticians generally, in making more accurate formant measurements, using commonly available speech analysis tools. Formant measurements are an important speech feature that are often examined in forensic casework, and are used widely in many other areas within the field of phonetics. However, the performance of software currently used by analysts has not been subject to detailed investigation. This thesis reports on a series of experiments that examine the influence that the analysis tools, analysis settings and speakers have on formant measurements. The influence of these three factors was assessed by examining formant measurement errors and their behaviour. This was done using both synthetic and real speech. The synthetic speech was generated with known formant values so that the measurement errors could be calculated precisely. To investigate the influence of different speakers on measurement performance, synthetic speakers were created with different third formant structures and with different glottal source signals. These speakers’ synthetic vowels were analysed using Praat’s normal formant measuring tool across a range of LPC orders. The real speech was from a subset of 186 speakers from the TIMIT corpus. The measurements from these speakers were compared with a set of hand-corrected reference formant values to establish the performance of four measurement tools across a range of analysis parameters and measurement strategies. The analysis of the measurement errors explored the relationships between the analysis tools, the analysis parameters and the speakers, and also examined how the errors varied over the vowel space. LPC order was found to have the greatest influence on the magnitude of the errors and their overall behaviour was closely associated with the underlying measurement process used by the tools. The performance of the formant trackers tended to be better than the simple Praat measuring tool, and allowing the LPC order to vary across tokens improved the performance for all tools. The performance was found to differ across speakers, and for each real speaker, the best performance was obtained when the measurements were made with a range of LPC orders, rather than being restricted to just one. The most significant guidance that arises from the results is that analysts should have an understanding of the basis of LPC analysis and know how it is applied to obtain formant measurements in the software that they use. They should also understand the influence of LPC order and the other analysis parameters concerning formant tracking. This will enable them to select the most appropriate settings and avoid making unreliable measurements

Anthropology of Color

The field of color categorization has always been intrinsically multi- and inter-disciplinary, since its beginnings in the nineteenth century. The main contribution of this book is to foster a new level of integration among different approaches to the anthropological study of color. The editors have put great effort into bringing together research from anthropology, linguistics, psychology, semiotics, and a variety of other fields, by promoting the exploration of the different but interacting and complementary ways in which these various perspectives model the domain of color experience. By so doing, they significantly promote the emergence of a coherent field of the anthropology of color