## 6 Discussion and Conclusions  
In China's megacities, the government demolishes downtown substandard housing and relocates residents (called relocatees in this study) to affordable large-scale residential areas in the suburbs of large cities. We have questions regarding this compulsory relocation and travel equity: is relocatees' travel equity different from that of non-relocatees? How does the travel equity alter over time (before and after the opening of a major shopping plaza nearby)? In the existing studies, it is difficult to obtain a good knowledge of the answers to those questions, especially for shopping trips in megacities during the suburbanization process in developing countries. To answer these questions, we conducted two surveys before and after the opening of Wanda Shopping Plaza, a large shopping mall near the study site in Shanghai. Statistical analysis is conducted to understand how relocatees and non-relocatees' shopping destination, travel time, and travel mode change before and after the opening of Wanda on the megacity periphery. Two travel-mode choice logit models are estimated and consumer surplus is calculated to measure travel-equity change over time. Results suggest that:  
(1) A total of 25% of shopping-related trips' destinations were located at Jiangqiao Business District (JBD) before the opening of Wanda. After the opening of Wanda, 21% of shopping-related trips' destinations was Wanda and the visit percentage of JBD declined sharply to 3%. In the heat maps in Figure 1, after the opening of Wanda, the hottest spot for shopping destinations moved from JBD to Wanda. (2) Shopping-related trips' average travel time decreases even though the average travel time for all trips increases (first two rows in Table 1) after Wanda's opening. In addition, the average travel time of relocatees is always significantly greater than that of non-relocatees, no matter whether for all trips or shopping-related trips, and no matter whether before or after Wanda's opening. This finding matches the conclusion in a previous study, which showed that from a travel-equity perspective, the relocation process and the development of the megacity periphery would have a greater impact on the travel of relocatees than other populations, and relocatees would have a lower travel quality than non-relocatees in developing countries [3]. The previous finding focused on overall travel purposes. What we find in this study can extend this from overall trips to shopping-related trips as well. (3) The share of shopping shuttle buses became less while the share of walking grew after the opening of Wanda, especially for shopping-related trips. This may be related to a nearer shopping mall providing higher accessibility by foot. Compared to relocatees, non-relocatees experience a larger increase in the car share, and their share of bus and metro use decreases for both regular trips and shopping-related trips (Table 1). Relocatees retain a similar share of car use for both periods. This may be because, compared to the relocatees, those who chose to live in the area are younger, richer, and more of them are working [3], thus they have more willingness, initiative, and ability to improve their travel condition. (4) Two travel-mode choice Logit models with samples before and after the opening of Wanda are estimated. Model results show that the median time value before Wanda opened was 0.41 CNY/min. After Wanda's opening, the value was 0.51 CNY/min (Table 3). Travel equity is measured by consumer surplus, which is calculated from the travel-mode choice models. Relocatees always have a lower travel quality for shopping-related trips no matter whether before or after the opening of Wanda Shopping Plaza. Over time, relocatees and non-relocatees are more likely to have a similar distribution shape. However, the travel equity between relocatees and non-relocatees for shopping-related trips becomes worse after the opening of Wanda Shopping Plaza.