Table 2.

Clustering quality measures of EEG data partition obtained by SDA.

Subject	Number of states	Cluster center type for state boundaries	Averaged over pairs of adjacent states
			Ward distance	Centroid distance	Silhouette coefficient	Calinski-Harabasz index	Davies-Bouldin index
Subj1	9	Mode	23,293	20.7	0.197	67.5	1.7
Subj2	8	Mode	17,853	12.4	0.102	59.4	2.9
Subj3	10	Mode	11,874	14.7	0.112	32.8	2.7
Subj1_surrogate	9	Median	771	3.6	0.002	1.4	13.2
Subj2_surrogate	8	Median	856	2.5	0.001	1.9	17.1
Subj3_surrogate	10	Mode	942	3.9	0.001	1.7	12.4
Average for 30 subjects Subj1–Subj30			12,509	10.9	0.127	68.7	3.1
Average for surrogate data			856	3.4	0.001	1.7	14.2