Abstract
This paper aims at examining sensitivity of an accessibility-based equity measure in the context of stochastic road network design problem. An equity optimization modeling framework based on bi-level programming approach is proposed where upper level problem addresses equity optimization with the constraint of network investment and lower level deals with user equilibrium model to reflect the route choice behavior with variations of link capacity improvement. An accessibility-based equity measure is specified by means of Gini coefficient. To verify the applicability of the model, an empirical study using data collected in Dalian City, China is carried out. Results demonstrate that the accessibility-based equity measure can be applied to measure the distributional difference of zonal accessibility. Comparative results also implicate that policy makers may need to trade-off among multi-objective situations involving the zonal accessibility level and the accessibility distribution.
