Table 1 The quantities that we use for expressing the skewness of the MPD

I) $\text{TC}\left(\mathcal{T}\right)=\sum _{\{u,v\}\in \Delta \left(S\right)}\mathit{\text{cost}}(u,v)$

II) $\text{CB}\left(\mathcal{T}\right)=\sum _{\{u,v\}\in \Delta \left(S\right)}\mathit{\text{cos}}{t}^3(u,v)$

III) $\forall e\in E,\text{TC}\left(e\right)=\sum _{\begin{array}{c}\{u,v\}\in \Delta \left(S\right)\\ e\in p(u,v)\end{array}}\mathit{\text{cost}}(u,v)$

IV) $\forall e\in E,\text{SQ}\left(e\right)=\sum _{\begin{array}{c}\{u,v\}\in \Delta \left(S\right)\\ e\in p(u,v)\end{array}}\mathit{\text{cos}}{t}^2(u,v)$

V) $\forall e\in E,\text{Mult}\left(e\right)=\sum _{\begin{array}{c}\{u,v\}\in \Delta \left(S\right)\\ e\in p(u,v)\end{array}}\text{TC}\left(u\right)·\text{TC}\left(v\right)$

VI) $\forall u\in S,\text{SM}\left(u\right)=\sum _{v\in S\setminus \left\{u\right\}}\mathit{\text{cost}}(u,v)·\text{TC}\left(v\right)$

VII) $\forall e\in E,{\mathit{\text{TC}}}_{\mathit{\text{sub}}}\left(e\right)=\sum _{\begin{array}{c}u\in S\left(e\right)\end{array}}\mathit{\text{cost}}(u,e)$

VIII) $\forall e\in E,{\mathit{\text{SQ}}}_{\mathit{\text{sub}}}\left(e\right)=\sum _{\begin{array}{c}u\in S\left(e\right)\end{array}}\mathit{\text{cos}}{t}^2(u,e)$

IX) $\forall e\in E,\text{PC}\left(e\right)=\sum _{\begin{array}{c}u\in S\end{array}}\mathit{\text{cost}}(u,e)$

X) $\forall e\in E,\text{PSQ}\left(e\right)=\sum _{\begin{array}{c}u\in S\end{array}}\mathit{\text{cos}}{t}^2(u,e)$

XI) $\forall e\in E,\text{QD}\left(e\right)=\sum _{u\in S\left(e\right)}{\left(\sum _{v\in S\left(e\right)\setminus \left\{u\right\}}\mathit{\text{cost}}(u,v)\right)}^2$