Canadian Raising in Chicagoland: The production and perception of a marginal contrast

In some North American English varieties the diphthong /aɪ/ has developed a distinctively higher nucleus before voiceless consonants and also before a flapped /t/. The phenomenon is known as Canadian Raising, as it was first described for Canadian English. We report on variation in the production and perception of this distinction in a group of female and male speakers from the Chicago area. We focus on the context before flapped /t/ and /d/. The production results show that there is a significant difference in the quality of both the nucleus and the offglide between these two contexts, albeit of a smaller magnitude than the difference observed before word-final voiceless and voiced consonants. In addition, we find a small difference in duration between diphthongs in the two pre-flap contexts. In perception, our subjects were only moderately successful in recognizing words in minimal pairs containing the target diphthong preceding a flap (as in writer vs rider), although with much higher than chance accuracy. A Quadratic Discriminant Analysis model classified the stimuli with substantially greater accuracy than our subjects. We conclude that in this English variety there is a contrast between a higher diphthong [ʌi] and a lower diphthong [aɪ], but this contrast is only marginal. This study contributes to our understanding of marginal contrasts in production and perception. The understanding of these contrasts has both theoretical and practical relevance.