14th International Congress of Phonetic Sciences (ICPhS-14)
San Francisco, CA, USA
Both at the beginning and at the end of their first year of education at the University of Aizu, a group of 80 native speakers of Japanese participating in an English language program were administered a five-alternative, forced-choice (5AFC) test to measure changes in their ability to distinguish between English voiceless fricatives The 80 pairs of the resulting 5-by-5 confusion matrices were submitted to cluster analysis over individuals. The two cluster solution was interpreted through an examination of changes in listener sensitivity and changes in response biases. Though an ANOVA gave no evidence that these two groups differed in their overall mean identification performance, there was a significant interaction showing that the members of these two groups used the response categories in a different manner. The signal-detection-theoretic analysis showed that the groups differed primarily in terms of bias toward particular fricative response categories, but also showed contrasting effects of vowel context on sensitivity versus response bias.
Bibliographic reference. Martens, William / Lambacher, Stephen (1999): "Individual differences in the acquisition of English fricative distinctions by native speakers of Japanese", In ICPhS-14, 129-132.