Table 5.

Mean (SD) duration ratio and lambda ratio for each tense–lax vowel pair as a function of condition.

Measure	Vowel pair	Habitual	Clear	Hearing impaired	Overenunciate
Duration ratio	æ–ε	0.70 (0.08)	0.67 (0.07)	0.72 (0.13)	0.67 (0.11)
	ɑ–ʌ	0.65 (0.13)	0.68 (0.17)	0.70 (0.17)	0.72 (0.17)
	i–ɪ	0.70 (0.14)	0.63 (0.15)	0.65 (0.11)	0.60 (0.12)
	u–ʊ	0.76 (0.19)	0.76 (0.21)	0.73 (0.23)	0.78 (0.24)
	Average	0.71 (0.08)	0.69 (0.09)	0.69 (0.08)	0.67 (0.07)
Lambda ratio	æ–ε	1.03 (0.44)	0.97 (0.32)	0.95 (0.30)	0.88 (0.36)
	ɑ–ʌ	1.40 (0.57)	1.40 (0.50)	1.58 (0.73)	1.90 (1.03)
	i–ɪ	0.93 (0.38)	1.08 (0.62)	1.22 (0.70)	1.55 (1.02)
	u–ʊ	1.06 (0.96)	0.81 (0.41)	0.74 (0.38)	0.85 (0.46)
	Average	0.98 (0.19)	0.92 (0.22)	0.97 (0.25)	1.00 (0.18)