TABLE 2.

Individual discrimination (d′) scores for the nine listeners, together with the mean value (rightmost column)

					Subject
Condition	1	2	3	4	5	6	7	8	9	Mean
AM quiet	2.25	1.78	1.47	2.01	2.23	2.52	2.22	2.18	2.11	2.09
AM +12 dB off	2.11	1.44	1.00	2.47	1.73	1.58	1.71	1.68	1.91	1.74
AM +12 dB on	2.30	1.61	1.53	3.08	1.98	2.14	1.98	2.19	2.18	2.11
AM +6 dB off	2.23	1.47	0.99	2.03	1.19	1.20	1.59	1.30	1.89	1.54
AM +6 dB on	2.02	1.45	0.99	2.21	1.53	1.90	2.00	2.12	2.28	1.83
AM 0 dB off	1.31	1.06	0.81	1.73	0.52	0.83	1.06	0.64	1.48	1.05
AM 0 dB on	1.10	0.84	0.60	1.74	1.16	1.15	1.32	1.07	1.47	1.16
AM −6 dB off	–	0.26	−0.33	0.23	–	–	–	–	–	0.05
AM −6 dB on	–	0.30	−0.19	0.15	–	–	–	–	–	0.09
FM quiet	2.15	1.69	1.52	2.48	2.38	2.31	1.89	1.57	2.00	2.00
FM +12 dB off	1.85	1.68	1.12	1.64	1.59	1.72	1.78	1.46	2.30	1.68
FM +12 dB on	1.59	1.48	1.37	1.92	2.05	1.78	1.72	1.86	2.21	1.78
FM +6 dB off	1.62	1.09	0.91	1.61	1.79	1.57	1.49	1.24	1.51	1.43
FM +6 dB on	0.84	0.96	0.94	1.75	1.76	1.31	1.12	1.52	1.83	1.34
FM 0 dB off	1.01	0.56	0.54	0.80	1.12	0.96	0.59	0.86	1.04	0.83
FM 0 dB on	0.35	0.12	0.24	0.88	1.08	0.74	0.54	0.96	0.78	0.63
FM −6 dB off	–	−0.12	−0.15	0.19	–	–	–	–	–	−0.03
FM −6 dB on	–	0.65	0.05	−0.15	–	–	–	–	–	0.18