Temporal Variability and Stability in Infant-Directed Sung Speech: Evidence for Language-specific Patterns.

In this paper, sung speech is used as a methodological tool to explore temporal variability in the timing of word-internal consonants and vowels. It is hypothesized that temporal variability/stability becomes clearer under the varying rhythmical conditions induced by song. This is explored crosslinguistically in German – a language that exhibits a potential vocalic quantity distinction – and the non-quantity languages French and Russian. Songs by non-professional singers, i.e. parents that sang to their infants aged 2 to 13 months in a non-laboratory setting, were recorded and analyzed. Vowel and consonant durations at syllable contacts of trochaic word types with ¦CVCV or ¦CVːCV structure were measured under varying rhythmical conditions. Evidence is provided that in German non-professional singing, the two syllable structures can be differentiated by two distinct temporal variability patterns: vocalic variability (and consonantal stability) was found to be dominant in ¦CVːCV structures whereas consonantal variability (and vocalic stability) was characteristic for ¦CVCV structures. In French and Russian, however, only vocalic variability seemed to apply. Additionally, findings suggest that the different temporal patterns found in German were also supported by the stability pattern at the tonal level. These results point to subtle (supra) segmental timing mechanisms in sung speech that affect temporal targets according to the specific prosodic nature of the language in question

Generalized Pareto Copulas: A Key to Multivariate Extremes

This paper reviews generalized Pareto copulas (GPC), which turn out to be a key to multivariate extreme value theory. Any GPC can be represented in an easy analytic way using a particular type of norm on $\mathbb{R}^d$, called $D$-norm. The characteristic property of a GPC is its exceedance stability. GPC might help to end the debate: What is a multivariate generalized Pareto distribution? We present an easy way how to simulate data from an arbitrary GPC and, thus, from an arbitrary generalized Pareto distribution. As an application we derive nonparametric estimates of the probability that a random vector, which follows a GPC, exceeds a high threshold, together with confidence intervals. A case study on joint exceedance probabilities for air pollutants completes the paper.Comment: 38 page

Communicative functions of rhythm in spoken discourse - the case of radio broadcasting

Time is one of the most precious resources in the audio-visual media. Journalists working in radio broadcasting are particularly subject to time constraints. Their message has to be passed on by the speech signal in a few minutes or seconds without visual support of written text or pictures. Therefore, the message has to be structured in a way that the most important aspects of the information are made prominent and interesting for the audience. On the other hand, journalists have to keep in time and need strategies to orient themselves in time in order to achieve exact timing of their spoken discourse. In this article, I lend support to the notion that the rhythmic structure of speech is one of the major tools for journalists to succeed in this endeavor. First, I review some of the literature on the nature of speech rhythm and its role for speech perception, language acquisition, processing and interaction. Second, the state of the art about what we know about rhythmic prominence in radio broadcasting is given. Finally, the idea will be advanced that speech rhythm, sometimes in conjunction with gesture, improves timing and time estimation in journalists speaking on air. A rich set of literature from different domains is presented in order to identify major questions and pathways for future research on speech rhythm in radio broadcasting.Le temps est une ressource précieuse dans les médias audio-visuels. Les journalistes qui travaillent à la radio sont particulièrement soumis aux contraintes temporelles. Leur message doit être diffusé en quelques minutes ou secondes sans le support visuel d'un texte ou des images. Ainsi, le message doit être structuré de telle façon que les aspects les plus importants seront proéminents dans le discours et intéressent l'audience. D'un autre point de vue, les journalistes ont besoin de bien contrôler le temps qu'ils mettent eux-mêmes pour prononcer leur discours et de s'orienter dans le temps pour ajuster le temps de leur intervention le plus précisément possible. Dans cette contribution, j'examine l'hypothèse que le rythme de la parole fournit les structures nécessaires pour la réussite dans ces défis journalistiques. Dans un premier temps, je présente la littérature sur la nature du rythme de la parole et son rôle dans la perception et le traitement de la parole, l'acquisition de la langue et dans l'interaction. Deuxièmement, je passe en revue les résultats principaux des études concernant la proéminence rythmique dans le phonostyle radiophonique. Finalement, l'hypothèse défendue est que le rythme de la parole, parfois concurremment avec les gestes, conduit à un meilleur timing et une meilleure estimation du temps par les journalistes eux-mêmes quand ils sont à l'antenne. L'article fournira au lecteur un aperçu détaillé et multidisciplinaire de la littérature et identifiera les enjeux et de nouvelles pistes pour la recherche future à propos du rythme de la parole à la radio

Temporal malleability to auditory feedback perturbation is modulated by rhythmic abilities and auditory acuity

Auditory feedback perturbation studies have indicated a link between feedback and feedforward mechanisms in speech production when participants compensate for applied shifts. In spectral perturbation studies, speakers with a higher perceptual auditory acuity typically compensate more than individuals with lower acuity. However, the reaction to feedback perturbation is unlikely to be merely a matter of perceptual acuity but also affected by the prediction and production of precise motor action. This interplay between prediction, perception, and motor execution seems to be crucial for the timing of speech and non-speech motor actions. In this study, to examine the relationship between the responses to temporally perturbed auditory feedback and rhythmic abilities, we tested 45 adult speakers on the one hand with a temporal auditory feedback perturbation paradigm, and on the other hand with rhythm perception and production tasks. The perturbation tasks temporally stretched and compressed segments (onset + vowel or vowel + coda) in fluent speech in real-time. This technique sheds light on the temporal representation and the production flexibility of timing mechanisms in fluent speech with respect to the structure of the syllable. The perception tasks contained staircase paradigms capturing duration discrimination abilities and beat-alignment judgments. The rhythm production tasks consisted of finger tapping tasks taken from the BAASTA tapping battery and additional speech tapping tasks. We found that both auditory acuity and motor stability in finger tapping affected responses to temporal auditory feedback perturbation. In general, speakers with higher auditory acuity and higher motor variability compensated more. However, we observed a different weighting of auditory acuity and motor stability dependent on the prosodic structure of the perturbed sequence and the nature of the response as purely online or adaptive. These findings shed light on the interplay of phonological structure with feedback and feedforward integration for timing mechanisms in speech

Conditional Tail Independence in Archimedean Copula Models

Consider a random vector $U$, whose distribution function coincides in its upper tail with that of an Archimedean copula. We report the fact that the conditional distribution of $U$, conditional on one of its components, has under a mild condition on the generator function independent upper tails, no matter what the unconditional tail behavior is. This finding is extended to Archimax copulas.Comment: 17 page

Strong Convergence of Multivariate Maxima

It is well known and readily seen that the maximum of $n$ independent and uniformly on $[0,1]$ distributed random variables, suitably standardised, converges in total variation distance, as $n$ increases, to the standard negative exponential distribution. We extend this result to higher dimensions by considering copulas. We show that the strong convergence result holds for copulas that are in a differential neighbourhood of a multivariate generalized Pareto copula. Sklar's theorem then implies convergence in variational distance of the maximum of $n$ independent and identically distributed random vectors with arbitrary common distribution function and (under conditions on the marginals) of its appropriately normalised version. We illustrate how these convergence results can be exploited to establish the almost-sure consistency of some estimation procedures for max-stable models, using sample maxima

Sound field control with hemi-cylindrical loudspeaker arrays

An acoustical model for the sound field generated by hemi-cylindrical loudspeaker arrays is presented and a method for beamforming with said arrays is derived. The sound field model is obtained by introducing two independent boundary conditions for the sound field of a single impinging plane wave. The model for the radiation from a single loudspeaker in the array is then obtained from the reciprocity principle. Various beam patterns are presented and the theoretically predicted sound field is evaluated as a function of frequency. The results are discussed and an experimental array prototype is presented

Reading Fluency in Children and Adolescents Who Stutter

Speech fluency is a major challenge for young persons who stutter. Reading aloud, in particular, puts high demands on fluency, not only regarding online text decoding and articulation, but also in terms of prosodic performance. A written text has to be segmented into a number of prosodic phrases with appropriate breaks. The present study examines to what extent reading fluency (decoding ability, articulation rate, and prosodic phrasing) may be altered in children (9–12 years) and adolescents (13–17 years) who stutter compared to matched control participants. Read speech of 52 children and adolescents who do and do not stutter was analyzed. Children and adolescents who stutter did not differ from their matched control groups regarding reading accuracy and articulation rate. However, children who stutter produced shorter pauses than their matched peers. Results on prosodic phrasing showed that children who stutter produced more major phrases than the control group and more intermediate phrases than adolescents who stutter. Participants who stutter also displayed a higher number of breath pauses. Generally, the number of disfluencies during reading was related to slower articulation rates and more prosodic boundaries. Furthermore, we found age-related changes in general measures of reading fluency (decoding ability and articulation rate), as well as the overall strength of prosodic boundaries and number of breath pauses. This study provides evidence for developmental stages in prosodic phrasing as well as for alterations in reading fluency in children who stutter