While the English sibilant fricatives can be well-differentiated by the centroid frequency of the frication noise alone, the Japanese sibilant fricatives cannot be. Measures of perceived spectral peak frequency and shape developed for stop bursts were adapted to describe sibilant fricative contrasts in English- and Japanese-speaking adults and children. These measures captured both the cross-language differences and more subtle inter-individual differences related to language-specific marking of gender. They could also be used in deriving a measure of robustness of contrast that captured cross-language differences in fricative development.
Bibliographic reference. Holliday, Jeffrey J. / Beckman, Mary E. / Mays, Chanelle (2010): "Did you say susi or shushi? measuring the emergence of robust fricative contrasts in English- and Japanese-acquiring children", In INTERSPEECH-2010, 1886-1889.