Figure 19
From: Gravity law in the Chinese highway freight transportation networks
![Figure 19](http://media.springernature.com/full/springer-static/image/art%3A10.1140%2Fepjds%2Fs13688-019-0216-6/MediaObjects/13688_2019_216_Fig19_HTML.jpg)
Testing the modified gravity law with population for the directed and undirected freight highway transportation networks constructed over five months. (a) Scatter plot of \(F_{ij}\) with respect to \((G_{i}/P_{i})^{\alpha_{1}}(G_{j}/P_{j})^{\alpha_{2}}/d_{ij}^{\alpha_{3}}\) for the directed network. (b) Binning plot of \(F_{ij}\) with respect to \((G_{i}/P_{i})^{\alpha_{1}}(G_{j}/P_{j})^{\alpha_{2}}/d_{ij}^{\alpha_{3}}\) for the directed network. (c) Scatter plot of \(W_{ij}\) with respect to \((G_{i}/P_{i})^{\alpha_{1}}(G_{j}/P_{j})^{\alpha_{2}}/d_{ij}^{\alpha_{3}}\) for the undirected network. (d) Binning plot of \(W_{ij}\) with respect to \((G_{i}/P_{i})^{\alpha_{1}}(G_{j}/P_{j})^{\alpha_{2}}/d_{ij}^{\alpha_{3}}\) for the undirected network