## 6 Discussion and Conclusions
This is the innovative contribution of this study, which quantitatively uses consumer surplus to evaluate the change in travel equity before and after the opening of a shopping plaza nearby, for shopping-related trips of relocatees and non-relocatees in city-peripheral large-scale-residential areas in a rapidly developing country. The results of this study are similar to the findings of previous studies; the wide inequity between different groups has become a common companion in the process of urban development [9; 11; 35; 36; 37; 38; 39; 40; 41; 42]. [PERSON] (1957) initially found that in the process of economic development, some regions achieved advanced development due to initial spatial advantages, and the developed regions formed a contrast with underdeveloped regions. This means that economic geographical development progress does not occur in every place and group at the same time and evenly, but is characterized by polarization [36; 39]. In this study, the relocatees in Shanghai experienced involuntary relocation, moving from the developed core area to the underdeveloped peripheral area, forming the group polarization in the peripheral area. The socio-economic conditions of relocates and non-relocatees show a polarized difference, which leads to a gap in travel for shopping trips. Briefly, inequity has become the companion of polarization [10; 35; 36; 39; 42]. Previous studies on travel inequity have supported the claim that the difference in travel reflects a variety of general socio-economic inequities, which usually occur in the process of urban growth and transformation [9; 11; 40; 43]. Travel inequity is found to be highly related with respondents' socio-economic attributes, such as income, gender, age, or immigration status [9; 37; 38], which is similar to the findings of this study. Overall, in the process of suburbanization of megacities in developing countries, there are various and wide inequitable phenomena. The findings of this study contribute to exploring the travel inequity of shopping trips in this process, focusing on the specific quantitative calculation results of the travel inequity of shopping trips between relocatees and non-relocatees, as well as the changes in the travel inequity of shopping trips of relocatees before and after the construction of commercial buildings. Besides this, due to the polarization effect, inequity may gradually expand over time [39; 44; 45]. Therefore, based on the findings of this study, a possible result is that the travel equity of relocatees and non-relocatees may become worse rather than better over time with economic growth and the development of the peripheral area. This is worth considering by the government and policymakers. Policy intervention has been confirmed to play a significant role in eliminating social inequity [36; 46; 47; 48; 49]. [PERSON] (1966) discussed the impact of government intervention on weakening regional inequity through a case study of Venezuela. Generally, when urban development enters the growth stage, the inequity in society would show an obvious dual structure, which is usually reflected in the gradual expansion of the socio-economic gap between different groups [36; 47; 50; 51; 52]. The government can weaken inequity through policy interventions [36; 46; 47; 50; 51; 52]. During this study, Shanghai was in the stage of urban growth; we found that the travel inequity of shopping trips in the peripheral areas was expanding through quantitative analysis. Appropriate government intervention is needed, controlling the travel inequity of shopping trips between relocatees and non-relocatees within an acceptable range. Therefore, the authors thought that the magnitude difference of consumer surplus between relocatees and non-relocatees would be a reference for possible travel subsidies that can be provided to the relocatees. The findings of this study can support policy decisions and urban transportation planning for large-scale residential areas in the suburbs of megacities.