The transportation has important influences to social development, and is the channel of geographical space and social economic activity. The developmental level of transportation determines the width and depth of geographical units interacting, and the development of transportation is an important factor of changing location dominance. Fully holding on the present status of transportation and the contribution of transportation to economic activity, it has important meanings for understanding economic phenomena and spatial distribution. There are many papers in the field of network analysis, which are concentrated on critical path method and using conventional indices of network analysis to evaluate network, such as the density of network, connecting rate, numbers of loop etc. Using the network analysis of GIS to evaluate regional transportation network is few, and using the network analysis of GIS to evaluate potential relationship between status of transportation network and regional economy is fewer. Having not considered such aspects as spatial distribution features of transportation networks and resident areas, the spatial influences of outside transportation modes on the features within the research regions as well as the different transit capacity of different transportation ways, the conventional measuring methods based on path analysis and network analysis are deficient to the description of regional transportation situation.
Connectivity of network nodes represents link numbers from one node to another node, and can be examined by constructing a matrix. Accessibility of network indicates the degree to which one can move in a network from every node to every other node. The accessibility matrix is the sum of all meaningful connectivity from the first order to the order equal to the network diameter. With the employment and optimization of the connectivity and accessibility of the network nodes to evaluate transportation network, this study successfully breaks through the limitation of the border of investigative area and, different transportation modes can also be taken into account.