Table 6.

In this table we compare the similarity of vascular trees obtained by standard CCO (sCCO) and improved CCO (iCCO) to the clinical CT data sets. The similarity values for individual features, but not the averages, can be compared to the HV and PV single-population similarities in Table 3.

Feature	PV/sCCO	HV/sCCO	PV/iCCO	HV/iCCO
Radius r	0.182	0.133	0.182	0.133
Radius decrease η r	0.363	0.246	0.363	0.246
Radius asymmetry σ r	0.376	0.206	0.376	0.206
Bif. exponent γ	0.219	0.150	0.219	0.150
Lengths l	0.662	0.615	0.614	0.574
Length decrease η l	0.943	0.939	0.902	0.887
Length asymmetry σ l	0.896	0.922	0.849	0.865
Angle φ a	0.444	0.479	0.779	0.581
Angle φ b	0.345	0.212	0.918	0.903
Angle φ c	0.865	0.784	0.875	0.902
Radius average	0.299	0.190	0.299	0.190
Length average	0.845	0.838	0.800	0.787
Angle average	0.545	0.494	0.857	0.802
Total average	0.588	0.542	0.687	0.634