Can L2 Pronunciation Be Evaluated without Reference to a Native Model? Pillai Scores for the Intrinsic Evaluation of L2 Vowels

Abstract

In this article, we explore the possibility of evaluating L2 pronunciation, and, more specifically, L2 vowels, without referring to a native model, i.e., intrinsically. Instead of comparing L2 vowel productions to native speakers’ productions, we use Pillai scores to measure the overlap between target vowel categories in L2 English (/iː/ — /ɪ/, /ɑː/ — /æ/, /ɜː/ — /ʌ/, /uː/ — /ʊ/) for L1 French, L1 Spanish, and L1 Italian learners (n = 40); and in L2 French (/y/ — /u/, /ø/ — /o/, /ø/ — /e/, /ɛ˜/ — /e /, /ɑ˜/ — /a/, /ɔ˜/ — /o/) for L1 English, L1 Spanish, and L1 Italian learners (n = 48). We assume that a greater amount of overlap within a contrast indicates assimilated categories in a learner’s production, whereas a smaller amount of overlap indicates the establishment of phonological categories and distinct realisations for members of the contrast. Pillai scores were significant predictors of native ratings of comprehensibility and/or nativelikeness for many of the contrasts considered. Despite some limitations and caveats, we argue that Pillai scores and similar methods for the intrinsic evaluation of L2 pronunciation can be used, (i) to avoid direct comparisons of L2 users’ performance with native monolinguals, following recent trends in SLA research; (ii) when comparable L1 data are not available; (iii) within longitudinal studies to track the progressive development of new phonological categories.