The acoustic-phonetic characteristics of speech sounds are influenced by their linguistic position in an utterance. Because of acoustic-phonetic differences between different speech sounds, sounds... Show moreThe acoustic-phonetic characteristics of speech sounds are influenced by their linguistic position in an utterance. Because of acoustic-phonetic differences between different speech sounds, sounds vary in the amount of speaker information they contain. However, do spectral and durational differences between various realizations of the same sound that were sampled from different linguistic positions also impact speaker information? We investigated speaker discrimination in [-focus] versus [+focus] word realizations. Twenty-one Dutch listeners participated in a same-different speaker discrimination task, using stimuli varying in focus, vowel ([a.], [u]), and word context ([._k], [v_t]), spoken by 11 different speakers. Results show that an effect of focus on speaker-dependent information was present, but limited to words containing [u]. Moreover, performance on [u] words was influenced by (interactions of) word context and trial type (same- vs. different-speaker). Context-dependent changes in a speech sound’s acoustics may affect its speaker-dependent information, albeit under specific conditions only. Show less
Filled pauses are widely considered as a relatively consistent feature of an individual’s speech. However, acoustic consistency has only been observed within single-session recordings. By comparing... Show moreFilled pauses are widely considered as a relatively consistent feature of an individual’s speech. However, acoustic consistency has only been observed within single-session recordings. By comparing filled pauses in two recordings made >2.5 years apart, this study investigates within-speaker consistency of the vowels in the filled pauses uh and um, in both first language (L1) Dutch and second language (L2) English, produced by student speakers who are known to converge in other speech features. Results show that despite minor within-speaker differences between languages, the spectral characteristics of filled pauses in L1 and L2 remained stable over time. Show less
In Moroccan Dutch, /s/ has been claimed to be pronounced as retracted [s] (towards /ʃ/) in certain consonant clusters. Recently, retracted s-pronunciation has also been attested in endogenous Dutch... Show moreIn Moroccan Dutch, /s/ has been claimed to be pronounced as retracted [s] (towards /ʃ/) in certain consonant clusters. Recently, retracted s-pronunciation has also been attested in endogenous Dutch. We tested empirically whether Moroccan Dutch [s] is indeed more retracted than endogenous Dutch [s] in relevant clusters. Additionally, we tested whether the inter-speaker variation of /s/ is smaller between Moroccan Dutch speakers than between endogenous Dutch speakers, as expected if retraction of /s/ would be used as identity marker in in-group conversations in Moroccan Dutch. The [s] realizations of 21 young, male Moroccan Dutch and 21 endogenous Dutch speakers were analyzed. Analyses of the spectral centre of gravity (CoG) show that both groups of speakers had more retracted pronunciations of [s] in typically retracting contexts than in typically non-retracting contexts. However, Moroccan Dutch speakers had higher CoG in both contexts than endogenous Dutch speakers, refuting the stronger retraction expected in Moroccan Dutch speakers. The inter-speaker variation was larger between Moroccan Dutch speakers than between endogenous-Dutch speakers, refuting the expected usage of /s/ retraction as a group identity marker. Show less
In forensic speech science, nasals are often reported to be particularly useful in characterizing speakers because of their low within-speaker and high between-speaker variability. However,... Show moreIn forensic speech science, nasals are often reported to be particularly useful in characterizing speakers because of their low within-speaker and high between-speaker variability. However, empirical acoustic data from nasal consonants indicate that there is a somewhat larger role for the oral cavity on nasal consonant acoustics than is generally predicted by acoustic models. For example, in read speech, nasal consonant acoustics show lingual coarticulation that differs by nasal consonant, and syllabic position also seems to affect realizations of nasal consonants within speakers. In the current exploratory study, the within and between-speaker variation in the most frequent nasals in Standard Dutch, /n/ and /m/, was investigated. Using 3,695 [n] and 3,291 [m] tokens sampled from 54 speakers’ spontaneous telephone utterances, linear mixed-effects modelling of acoustic-phonetic features showed effects of phonetic context that differed by nasal consonant and by syllabic position. A following speaker-classification test using multinomial logistic regression on the acoustic-phonetic features seems to indicate that nasals displaying larger effects of phonetic context also perform slightly better in speaker classification, although differences were minor. This might be caused by between-speaker variation in the degree and timing of lingual coarticulatory gestures. Show less
Fluency in terms of speed of speech and (lack of) hesitations such assilent and filled pauses (‘uhm’s) is part of oral proficiency. Languageassessment rubrics therefore include aspects of fluency.... Show moreFluency in terms of speed of speech and (lack of) hesitations such assilent and filled pauses (‘uhm’s) is part of oral proficiency. Languageassessment rubrics therefore include aspects of fluency. Measuringfluency, however, is highly time-consuming because of the manuallabour involved. The current paper aims to automatically measureaspects of L2 fluency, including filled pauses, in both Dutch andEnglish. A revised existing script and a new script for filled pausesare tested on accuracy. We also gauged whether the outcomes ofthe new script could be used for language assessment purposes byrelating the outcomes to human judgements. Without furtherinvestigations, the current script should not (yet) be used for thepurpose of assessing fluency automatically in (high-stakes) oralproficiency assessment. However, the performance of the scriptsfor measuring aspects of fluency globally and quickly are promising,especially given their stability in accuracy on new corpora. Show less
Fluency in terms of speed of speech and (lack of) hesitations such as silent and filled pauses (‘uhm’s) is part of oral proficiency. Language assessment rubrics therefore include aspects of fluency... Show moreFluency in terms of speed of speech and (lack of) hesitations such as silent and filled pauses (‘uhm’s) is part of oral proficiency. Language assessment rubrics therefore include aspects of fluency. Measuring fluency, however, is highly time-consuming because of the manual labour involved. The current paper aims to automatically measure aspects of L2 fluency, including filled pauses, in both Dutch and English. A revised existing script and a new script for filled pauses are tested on accuracy. We also gauged whether the outcomes of the new script could be used for language assessment purposes by relating the outcomes to human judgements. Without further investigations, the current script should not (yet) be used for the purpose of assessing fluency automatically in (high-stakes) oral proficiency assessment. However, the performance of the scripts for measuring aspects of fluency globally and quickly are promising, especially given their stability in accuracy on new corpora. Show less
In forensisch zaakonderzoek komt steeds vaker spraakmateriaal in verschillende talen voor. Dit roept de vraag op of er taalonafhankelijke spreker-specifieke kenmerken zijn. De bilabiale nasaal /m/... Show moreIn forensisch zaakonderzoek komt steeds vaker spraakmateriaal in verschillende talen voor. Dit roept de vraag op of er taalonafhankelijke spreker-specifieke kenmerken zijn. De bilabiale nasaal /m/ is één van de meest spreker-specifieke segmenten, wat wordt toegeschreven aan de rigiditeit van de neusholte [1]. Tegelijkertijd is de mondholte ook betrokken bij de productie en heeft de tong daarbij geen vaste positie [2]. Hierdoor is er ruimte voor binnen-sprekervariatie, die mogelijk taalafhankelijk is. Wij onderzochten in hoeverre de realisatie van /m/ verschilt tussen de eerste (L1) en tweede taal (L2) van meertalige sprekers.Er zijn monologen gebruikt van 53 vrouwelijke sprekers uit D-LUCEA [3], in hun L1 Nederlands en L2 Engels. De sprekers waren eerstejaarsstudenten van University College Utrecht en hadden een bovengemiddelde beheersing van het Engels. De nasalen werden gesegmenteerd in Praat en geanalyseerd op verschillende akoestische kenmerken.De resultaten laten zien dat de verschillen tussen de realisaties in de L1 en L2 minimaal zijn. Alleen de tweede nasale formant (N2) liet een taalverschil zien: hoger in de L2 dan in de L1. Sprekers verschilden in de mate waarin ze deze verschuiving vertoonden en voor sommigen was het resultaat in tegengestelde richting.Hoewel de gevonden L1−L2 verschillen in de uitspraak van de /m/ klein zijn, lijkt de bilabiale nasaal niet geheel taalonafhankelijk. De N2 wordt gerelateerd aan de mond- en neusholte [4], wat duidt op een aanpassing in de productie. Rekening houdend met deze aanpassing zou de /m/ bruikbaar kunnen zijn in meertalige sprekervergelijkingen. Vervolgstappen zijn om dit te onderzoeken met sprekerclassificatie. Show less
It has been claimed that filled pauses are transferred from the first (L1) into the second language (L2), suggesting that they are not directly learned by L2 speakers. This would make them usable... Show moreIt has been claimed that filled pauses are transferred from the first (L1) into the second language (L2), suggesting that they are not directly learned by L2 speakers. This would make them usable for cross-linguistic forensic speaker comparisons. However, under the alternative hypothesis that vowels in the L2 are learnable, L2 speakers adapt their pronunciation. This study investigated whether individuals remain consistent in their filled pause realization across languages, by comparing filled pauses (uh, um) in L1 Dutch and L2 English by 58 females. Next to the effect of language, effects of the filled pauses' position in the utterance were considered, as these are expected to affect acoustics and also relate to fluency. Mixed-effects models showed that, whereas duration and fundamental frequency remained similar across languages, vowel realization was language-dependent. Speakers used um relatively more often in English than Dutch, whereas previous research described speakers to be consistent in their um:uh ratio across languages. Results furthermore showed that filled-pause acoustics in the L1 and L2 depend on the position in the utterance. Because filled pause realization is partially adapted to the L2, their use as a feature for cross-linguistic forensic speaker comparisons may be restricted. Show less
