Tukey comparisons showed significant differences between similar and new vowels (/oe/-/ɔ/: p<.001, /oe/-/ɛ/: p <.001, /y/-/ɔ/: p = .042, /y/-/ɛ/: p<.001, Bonferroni-adjusted), indicating that students got much less accent when producing similar vowels (mean for /ɔ/ = 5.49, mean for /ɛ/ = 5.71) than new vowels (mean for /y/ = 4.68, mean for /oe/ = 4.6).
no distinctions were found within similar (/ɔ/-/ɛ/: p = 2.29, Bonferroni-adjusted) or new vowels (/oe/-/y/: p = 4.74, Bonferroniadjusted).