Table 3.

The results of network centrality.

City	Out-degree	In-degree	Betweenness	In-Closeness	Out-Closeness
Chongqing	15	15	3.63	100.00	100.00
Chengdu	15	12	1.25	83.33	100.00
Zigong	15	12	3.06	83.33	100.00
Luzhou	14	15	2.93	100.00	93.75
Deyang	15	13	1.91	88.24	100.00
Mianyang	14	12	2.00	83.33	93.75
Suining	12	12	1.04	83.33	83.33
Neijiang	14	10	0.69	75.00	93.75
Leshan	10	13	0.65	88.24	75.00
Nanchong	15	13	2.27	88.24	100.00
Meishan	8	15	0.76	100.00	68.18
Yibin	10	15	1.38	100.00	75.00
Guang’an	13	15	2.81	100.00	88.24
Dazhou	15	10	0.83	75.00	100.00
Ya’an	12	14	2.26	93.75	83.33
Ziyang	13	14	2.54	93.75	88.24