Table 2. AUC values for natural scenes.

Nr. of subjects Nr. of images	1	2	4	7	13	25	47	Subject-specific
Image-specific	0.689	0.724	0.748	0.763	0.778	0.791	0.802
63	0.703	0.715	0.723	0.726	0.727	0.728	0.729	0.732
32	0.693	0.708	0.718	0.722	0.724	0.726	0.726	0.722
16	0.678	0.696	0.709	0.715	0.719	0.721	0.722	0.707
8	0.662	0.680	0.695	0.704	0.709	0.713	0.715	0.689
4	0.647	0.661	0.677	0.688	0.696	0.701	0.704	0.674
2	0.636	0.645	0.657	0.668	0.680	0.686	0.690	0.659
1	0.619	0.631	0.643	0.651	0.660	0.668	0.675	0.640