Study of Urban System Spatial Interaction Based on Microblog Data: A Case of Huaihe River Basin, China

Table 5

Ratio of inflow and outflow.

Grade	City	Inflow and outflow ratio
1	Luohe	>300
2	Kaifeng, Huainan	51–300
3	Bozhou, Yangzhou	6–50
4	Xinyang, Fuyang, Suzhou, Jining, Lianyungang Pingdingshan, Xuchang, Zhoukou, Zhumadian, Shangqiu	1–5
5	Heze, Huaibei, Bengbu, Lu'an, Huaiyin, Suqian, Xuzhou, Zaozhuang, Linyi, Rizhao, Yancheng	<1