Postvocalic /r/-deletion in standard dutch: how experimental phonology can profit from ASR technology

In this study automatic speech recognition (ASR) techniques were used to substantiate the findings of phonological research on postvocalic /r/-deletion in Standard Dutch. A database containing spontaneous speech utterances stemming from man-machine interactions in an automatic train-table inquiry system was used for this purpose. Pronunciation variants with and without /r/ were automatically generated on the basis of our specification of the phonological rule of /r/-deletion and were then included in the lexicon of a continuous speech recognizer (CSR) which was used in forced recognition mode. The results show that in a corpus containing 214,102 words, in which /r/-deletion could be applied 16,865 times, it was actually applied in 47.6% of the cases. This is a high percentage of occurrence for a phenomenon that has so sporadically been described. Furthermore, the results substantiate our rule specification: /r/-deletion occurs more often after schwa than after any other vowel.