A previous study showed that a discriminant model using variables of the rise and steady+decay durations of frication could successfully classify the fricative /s/ and affricate /ts/ pronounced at a normal speaking rate. To examine the model's general ability regarding speaking rates, it was examined with /s/ and /ts/ at various speaking rates. The model was able to classify the consonants at both fast and slow speaking rates with almost the same error ratio at the normal speaking rate. However, it could not classify the consonants when the data of all speaking rates were combined. These results suggest that the discriminant model can capture the homologous structure of /s/ and /ts/ at each speaking rate but that it requires revision to classify /s/ and /ts/ across a wide range of speaking rates.
