No abstract

Purpose Four measures of children’s developing robustness of phonological contrast were compared to see how they correlated with age, with vocabulary size, and with adult listeners’ “correctness” ratings. Method Word-initial sibilant fricative productions from 81 two- to five-year-old children and 20 adults were phonetically transcribed and acoustically analyzed. Four measures of robustness of contrast were calculated for each speaker based on the centroid frequency measured from each fricative token. Productions from different children that were transcribed as correct were then used as stimuli in a perception experiment in which adult listeners rated the goodness of each production. Results Results showed that the degree of category overlap, quantified as the percentage of a child’s productions whose category could be correctly predicted from the output of a mixed effects logistic regression model, was the measure that correlated best with listeners’ goodness judgments. Conclusions Even when children’s productions have been transcribed as “correct”, adult listeners are sensitive to within-category variation quantified by the child’s degree of category overlap. Further research is needed to explore the relationship between the age of a child and adults’ sensitivity to different types of within-category variation in children’s speech.

The current study reports the results of a perception experiment in which 20 naive native Mandarin listeners classified and rated the goodness of Korean stops /p, t, k, p(h), t(h), k(h), p*, t*, k*/, affricates /tɕ, tɕ*, tɕ(h)/, and fricatives /s(h), s*/ in terms of Mandarin segmental categories. It was found that listeners were sensitive to the voice onset time dimension of Korean stops and the presence of aspiration in Korean affricates, but Korean lenis and aspirated obstruents were generally assimilated to a single Mandarin category because the f0 cue differentiating them is not relevant to any Mandarin segmental contrast. The affricates were perceived as alveolopalatal and postalveolar more often than alveolar. The perception of fricatives was strongly influenced by vowel context, as the two fricatives were often perceived as different categories before /a/, but as the same category more often before /i/ and /u/. The results for the affricates and fricatives may be partly explained by Mandarin phonotactic constraints that prohibit alveolar and postalveolar consonants before /i/ and alveolopalatal consonants before /a/ or /u/.

The neutralization of /sʰ/ and /s*/ in Gyeongsang dialects is a culturally salient stereotype that has received relatively little attention in the phonetic literature. The current study is a more extensive acoustic comparison of the sibilant fricative productions of Seoul and Gyeongsang dialect speakers. The data presented here suggest that, at least for young Seoul and Daegu speakers, there are few inter-dialectal differences in sibilant fricative production. These conclusions are supported by the output of mixed effects logistic regression models that used aspiration duration, spectral mean of the frication noise, and H1-H2 of the following vowel to predict fricative type in each dialect. The clearest dialect difference was that Daegu speakers' /sʰ/ and /s*/ productions had overall shorter aspiration durations than those of Seoul speakers, suggesting the opposite of the traditional "/s*/ produced as [sʰ]" stereotype of Gyeongsang dialects. Further work is needed to investigate whether /sʰ/-/s*/ neutralization in Daegu is perceptual rather than acoustic in nature.