Table 4.

Summary of results from repeated-measures analysis of variance tests evaluating main effects of noise type, similarity, and their interaction on vowel features.

Vowel Feature	Main and interaction effects of noise type and similarity on vowel features
		F	p	Pairwise differences between similarity conditions			p
F1	Noise	14.04	< .001	Sibilant–quiet		—
				Sibilant–vowel		—
				Vowel–quiet		14 Hz	< .001
	Similarity	2.68	.090	—
	Noise × Vowel	2.57	.096	—
	Noise × Similarity	0.69	.502	—
	Vowel × Similarity	1.21	.302	—
	Noise × Vowel × Similarity	0.65	.629	—
F2	Noise	5.18	.013	—
	Similarity	4.52	.020	—
	Noise × Vowel	2.86	.076	—
	Noise × Similarity	0.72	.580	—
	Vowel × Similarity	3.91	.033	—
	Noise × Vowel × Similarity	2.99	.027	—
Relative intensity	Noise	21.81	< .001	Sibilant–quiet		0.6 dB	< .001
				Sibilant–vowel		—
				Vowel–quiet		0.7 dB	< .0005
	Similarity	5.12	.013	—
	Noise × Vowel	9.99	.001	/a/ - /æ/	Sibilant–quiet	—
					Sibilant–vowel	—
					Vowel–quiet	0.4 dB	< .001
	Noise × Similarity	3.84	.008	Vowel–quiet	Med–low	—
					High–low	—
					High–medium	—
				Sibilant–quiet	Med–low	—
					High–low	—
					High–medium	—
				Vowel - Sibilant	Med–low	—
					High–low	−0.4 dB	< .01
					High–medium	0.5 dB	< .0167
	Vowel × Similarity	0.18	.839	—
	Noise × Vowel × Similarity	1.66	.173	—
Vowel duration	Noise	2.86	.080	—
	Similarity	10.29	< .001	Medium–low		6 ms	< .0167
				High–low		—
				High–medium		—
	Noise × Vowel	3.66	.040	—
	Noise × Similarity	2.10	.094	—
	Vowel × Similarity	1.15	.333	—
	Noise × Vowel × Similarity	2.86	.032	—

Note. The main effects of phoneme (/a/ vs. /æ/) are not displayed as these have been previously documented in the research literature. Dashes in the table denote nonsignificant findings.