Table 5. Global complexity metrics of 3D knee kinematics according the gender.

Complexity measures	Men group	Women group
Fraction of points on the class boundary (N1)	0.42	0.55
Ratio of average intra/inter class nearest neighbor distance (N2)	0.87	0.93
Error rate of a nearest neighbor distance (N3)	0.24	0.42
Non-linearity of 1-nearest neighbor classifier (N4)	0.06	0.20
Fraction of maximum covering spheres (T1)	1	1
Average number of points per dimension (T2)	0.47	0.68