## 2 Literature Review  
The population group, relocatees, results from a special type of passive residential relocation [4]. Controversial issues are raised in both residential displacement and passive relocation. The former is common in developed countries due to urban regeneration, while the latter occurs mainly in developing countries. [4]. One of the issues is the travel-behavior change and dissatisfaction towards the transport services of the new home area after the relocation [2; 5]. Previously, researchers have paid much attention to residential mobility and displacement in Western countries. Much research has been performed in this area. In this section, we do not overly focus on residential displacement in developed countries (for details, please refer to [4; 6; 7]). Instead, the passive relocation in Eastern countries will be our main focus. Eastern megacities' involuntary relocation has mainly occurred in past decades. Multiple studies have focused on the relocatees' travel behavior and welfare (for a detailed review of such relocation and travel behavior of the relocatees and non-relocatees in Eastern and developing countries, please see [2; 3; 4]). However, only a little research has focused on relocatees' travel equity and quality issues after the relocation in these peripheral megacity areas in developing countries. According to previous research, mobility inequality occurs in developing countries [8; 9; 10; 11]. In China, the decreased mobility reduces involuntary movers' perceptions of urban livibility [12], and moving to the city periphery reduced happiness for involuntary movers [13; 14]. [PERSON] and [PERSON] found that in one trip, relocatees' travel quality was 6.88 CNY/person lower than that of voluntary movers when choosing a travel mode, which was related to the travel-equity issue. It showed that from a travel-equity perspective, the relocation process and the development of megacity periphery would have a greater impact on the travel of relocatees than on other people [3; 5]. So far, most studies that investigated this topic have used the overall or commute trips in developing countries. Only some studies have focused on shopping-related trips. They studied the travel behavior to retail centers and assessed local or regional impacts of a new mall on the road traffic, focusing on trip generation (trip frequency and duration) and trip types [15; 16; 17; 18; 19], etc. [PERSON] and [PERSON] examined changes in shopping-related trips of metropolitan residents after the establishment of a new shopping area in Tampines New Town, which was out of the center of Singapore. In Tampines Regional Center, many people used to buy daily necessities in the new town and go shopping for other goods in the city center. After the opening of the new shopping area, they could partially meet their needs for both in the local retail stores. Those out-shoppers who frequently visited the city center and neighborhood centers would be likely to reduce their out-shopping trips after the center was fully developed [20]. As for travel-mode choice, [PERSON] and [PERSON] found that local retail stores had the least impact on car usage. \"Most of the walks to stores did, in fact, appear to substitute for driving\" in Austin [21]. In Prague, [PERSON] et al., used the data before and after retail land use shifted to illustrate how shopping travel behaviors shifted with it. They found some apparent changes: residents tended to shop less frequently but for a longer period of time, and they also walked to the store less. After more automobile-oriented developments were constructed, residents disproportionately shifted their travel patterns to increasingly use the car [22]. When studying the influence of retail de-concentration on trips to hypermarkets in Prague, [PERSON] found that, among the people who would shop by car, which accounted for 47%, almost all (92%) of them still shopped by car.