Table 2 Network topology inference models.
Indicator | Connotation | Geographical Significance | Equation | |
|---|---|---|---|---|
Degree | The average number of edges connected to all nodes in the network | The activity level of oil and natural gas trade networks | \({C}_{d}(x)=d(x)\) | (1) |
Weighted Degree | The average weight of the connecting edges of all nodes in the network | The scale of the oil and natural gas trade networks | \({DC}=\frac{1}{n-1}{k}_{i}\) | (2) |
Graph density | The ratio of the actual number of edges possessed by the network to the maximum possible number of edges | The completeness of the oil and natural gas trade networks | \(d(G)=\frac{2m}{n(n-1)}\) | (3) |
Average clustering coefficient | The ratio of the number of edges between a node and all its adjacent points to the maximum possible number of edges | Parameters of oil and natural gas trade networks aggregation | \(C=\frac{1}{n}\mathop{\sum }\limits_{i=1}^{n}\frac{{\sum }_{i,k,h\in {N}_{i}}{e}_{{jk}}{e}_{{kh}}}{{k}_{i}({k}_{i}-1)/2}\) | (4) |
Average path length | The average distance between any two nodes | The accessibility efficiency of oil and natural gas trade networks | \(L=\frac{{\sum }_{i\ne j}{d}_{{ij}}}{N(N-1)}\) | (5) |
