Peter Ladefoged

Bio: Peter Ladefoged is an academic researcher from University of California, Los Angeles. The author has contributed to research in topics: Vowel & Formant. The author has an hindex of 45, co-authored 142 publications receiving 13553 citations. Previous affiliations of Peter Ladefoged include University of Edinburgh.

A course in phonetics

Abstract: Part I Introductory concepts: articulatory phonetics phonology and phonetic transcription. Part II English phonetics: the Consonants of English English vowels English words and sentences. Part III General phonetics: airstream mechanisms and phonation types place and manner of articulation acoustic phonetics vowels and vowel-like articulations syllables and suprasegmental features linguistic phonetics the international phonetic alphabet feature hierarchy performance exercises.

The Sounds of the World's Languages

Abstract: List of Figures. List of Tables. Acknowledgments. 1. The Sounds of the Worlda s Languages. 2. Places of Articulation. 3. Stops. 4. Nasals and Nasalized Consonants. 5. Fricatives. 6. Laterals. 7. Rhotics. 8. Clicks. 9. Vowels. 10. Multiple Articulatory Gestures. References. Index.

Information Conveyed by Vowels

Abstract: Most speech sounds may be said to convey three kinds of information: linguistic information which enables the listener to identify the words that are being used; socio‐linguistic information, which enables him to appreciate something about the background of the speaker; and personal information which helps to identify the speaker. An experiment has been carried out which shows that the linguistic information conveyed by a vowel sound does not depend on the absolute values of its formant frequencies, but on the relationship between the formant frequencies for that vowel and the formant frequencies of other vowels pronounced by that speaker. Six versions of the sentence Please say what this word is were synthesized on a Parametric Artificial Talking device. Four test words of the form b‐(vowel)‐t were also synthesized. It is shown that the identification of the test word depends on the formant structure of the introductory sentence. Some psychological implications of this experiment are discussed, and hypotheses are put forward concerning the ways in which all three kinds of information are conveyed by vowels.

The Sound Pattern of English

Abstract: Since this classic work in phonology was published in 1968, there has been no other book that gives as broad a view of the subject, combining generally applicable theoretical contributions with analysis of the details of a single language. The theoretical issues raised in The Sound Pattern of English continue to be critical to current phonology, and in many instances the solutions proposed by Chomsky and Halle have yet to be improved upon.Noam Chomsky and Morris Halle are Institute Professors of Linguistics and Philosophy at MIT.

Foundations of the PARAFAC procedure: Models and conditions for an "explanatory" multi-model factor analysis

Abstract: Simple structure and other common principles of factor rotation do not in general provide strong grounds for attributing explanatory significance to the factors which they select. In contrast, it is shown that an extension of Cattell's principle of rotation to Proportional Profiles (PP) offers a basis for determining explanatory factors for three-way or higher order multi-mode data. Conceptual models are developed for two basic patterns of multi-mode data variation, systemand object-variation, and PP analysis is found to apply in the system-variation case. Although PP was originally formulated as a principle of rotation to be used with classic two-way factor analysis, it is shown to embody a latent three-mode factor model, which is here made explicit and generalized frown two to N "parallel occasions". As originally formulated, PP rotation was restricted to orthogonal factors. The generalized PP model is demonstrated to give unique "correct" solutions with oblique, non-simple structure, and even non-linear factor structures. A series of tests, conducted with synthetic data of known factor composition, demonstrate the capabilities of linear and non-linear versions of the model, provide data on the minimal necessary conditions of uniqueness, and reveal the properties of the analysis procedures when these minimal conditions are not fulfilled. In addition, a mathematical proof is presented for the uniqueness of the solution given certain conditions on the data. Three-mode PP factor analysis is applied to a three-way set of real data consisting of the fundamental and first three formant frequencies of 11 persons saying 8 vowels. A unique solution is extracted, consisting of three factors which are highly meaningful and consistent with prior knowledge and theory concerning vowel quality. The relationships between the three-mode PP model and Tucker's multi-modal model, McDonald's non-linear model and Carroll and Chang's multi-dimensional scaling model are explored.

Perceptual linear predictive (PLP) analysis of speech

Abstract: A new technique for the analysis of speech, the perceptual linear predictive (PLP) technique, is presented and examined. This technique uses three concepts from the psychophysics of hearing to derive an estimate of the auditory spectrum: (1) the critical-band spectral resolution, (2) the equal-loudness curve, and (3) the intensity-loudness power law. The auditory spectrum is then approximated by an autoregressive all-pole model. A 5th-order all-pole model is effective in suppressing speaker-dependent details of the auditory spectrum. In comparison with conventional linear predictive (LP) analysis, PLP analysis is more consistent with human hearing. The effective second formant F2' and the 3.5-Bark spectral-peak integration theories of vowel perception are well accounted for. PLP analysis is computationally efficient and yields a low-dimensional representation of speech. These properties are found to be useful in speaker-independent automatic-speech recognition.