Settlement intention refers to immigrants’ willingness to reside permanently in the society to which they move, and a great deal of research has considered the factors that influence the settlement intentions of immigrants. The research objects include not only migrants from rural areas to cities in the process of urbanization, but also international immigrants in the process of globalization. How to design and formulate relevant policies to promote the settlement and integration of immigrants is a common problem that is faced by societies in places that receive immigrants. Therefore, the issue is also a common focus of researchers. Strictly speaking, investigating the actual settlement behavior of immigrants must rely on large-scale and longitudinal survey data. However, such data are very difficult to obtain, and especially in developing countries. Thus, an alternative approach is to understand the motivations of potential settlers and returnees by analyzing the settlement intentions of immigrants. A large number of studies have examined the determinants of immigrants’ permanent settlement.
1. Socioeconomic, Cultural, and Institutional Perspectives and Long-Term Settlement Intention
A review of the existing academic analyses on the factors that influence the settlement intentions of immigrants indicates that there are three types of perspectives: economic rationality, and cultural and institutional explanations.
From the perspective of economic rationality, the most important factor in the decisions of immigrants to settle in a certain country (region) comes from the difference between the economic returns of the inflowing country and the exporting country in terms of human capital, according to the theory of neoclassical economics
[1][2]. If the economic returns of the inflowing country are better than the exporting country, for rational considerations, they will move from the exporting country to the inflowing country in order to obtain better returns
[3][4]. After that, the economic integration status in the immigration country will directly affect whether immigrants make long-term settlement decisions. The more successful they are as individuals in the immigrant-receiving country, the more likely they are to settle down in the country
[4]. Once the economic benefits of the immigrant-receiving place are reduced, or even lower than that of the country of origin, those who have migrated for economic reasons will migrate back to their own country again. Usually, those who have received a good education and those with stronger input language skills have more human capital and are more likely to obtain better jobs and better returns in the immigrant-receiving place. Therefore, they usually fare better than people with low education and poor language skills and are more inclined to settle down. Generally, there is a positive correlation between education level and settlement intention. The higher an individual’s education level is, the more likely he/she is to settle down in the society to which he/she immigrated. The logic behind this is that the more educated people are, the easier it is for them to find a good job in the labor market of the society, and thus, they can improve their social living conditions. In addition, their values are less fixed, they learn languages and cultural customs faster, and they can more easily integrate into the society of the immigrant-receiving place
[5][6][7][8].
From the cultural perspective, the amount and quality of the social interaction in the immigrant-receiving place can significantly affect future settlement intentions
[9]. In the early stage of immigration, having many relatives and friends in the society of the immigrant-receiving place helps immigrants to become established there. People from the same ethnic group and region can provide not only material help, such as a place to live, sustenance, and basic living conditions, but also emotional support to help immigrants through the initial period of loneliness
[10][11][12][13][14]. After becoming established in the society of the immigrant-receiving place, the immigrant’s ability to learn the language, culture, and customs, find a job in mainstream society, strengthen communication with mainstream social groups, and form a new support network are important factors in the decision as to whether to stay. If immigrants restrict their activities and living circles to their original ethnic group, then they may never integrate into mainstream society and will be excluded from the local society, which may eventually affect their willingness to settle down. If immigrants expand their circle, then they will be able to enter, receive recognition from and integrate into mainstream society, obtain various resources and services from the local society, and, finally, psychologically identify with the local society and gain the local identity.
Many studies have revealed a possible nonlinear relationship between age and willingness to settle down. With increasing age, the settlement intention increases, but after a certain age, the settlement intention decreases
[15]. This may be because young people have better social-adaptation abilities and are more willing to accept challenges, while older people’s abilities begin to decline in all aspects. When older individuals are hindered in the immigrant-receiving places, they are more inclined to return to their hometowns. In terms of marital status, there is no agreement regarding its effect on immigrants’ willingness to settle down. Some scholars believe that, when confronted with migration and remigration, married people consider various issues, such as the separation of the family members and children’s education, and so they face more restrictive factors than unmarried people, with a resulting negative impact on the decision of residence
[8][16][17][18]. Other scholars reckon that the economic benefits brought about by migration and remigration may far outweigh the losses caused by family separation and do not have a significant impact on migration and residence
[19][20][21][22].
From the perspective of the institutional setting, social institutions and policies may be significant variables that affect immigrants’ future settlement intentions. Numerous studies from China on the willingness of the floating population to settle down in cities have revealed how China’s household registration system and barriers reduce the willingness of the floating population to settle down in cities
[23][24][25]. Studies on international migration also reveal how the rigidity of the immigration system and policies in the society of the immigrant-receiving place affect immigrants’ integration into society and ultimately influence their willingness to settle down permanently
[26].
Although these studies explore many factors that influence the settlement intentions of immigrants from different perspectives, they do not address an interesting phenomenon that widely exists both in the domestic floating population and among international migrants, which is that the health status of migrants who settle down in immigrant-receiving places is better than that of those who move back, and even better than that of local residents. For example, Hispanic immigrants in the United States are healthier than native Americans, they are less likely to suffer from chronic diseases and mental disorders, and they have a lower mortality rate
[25][27][28][29]. In contrast, the health status of those who have returned to their hometowns is relatively worse, which cannot be effectively explained from the above research perspectives.
2. Health, Migration, and Long-Term Settlement Intention
Scholars have proposed two hypotheses to explain this paradox. The first hypothesis is the “healthy migrant” hypothesis, which states that migrants represent a positively selected group of individuals with respect to health, relative to the general populations in origin societies
[8][30]. This selection process makes immigrants stand out in terms of health levels when compared with the general populations in destination countries
[31]. This implies that healthy immigrants are more willing to migrate than less healthy immigrants
[8][25][32]. This hypothesis highlights the important role of health in migration decisions. Why is health so significant for migration? This is because the process of migration is often difficult and consumes physical strength, and it interrupts individuals’ normal lives and requires them to readapt to the society to which they move. The process of migration is painful, and those in poor health are less willing to migrate. In addition, immigrants are often required to undertake manual labor in the immigrant-receiving society. Those who are healthier, more tolerant of such jobs, and financially successful are more willing to migrate. In theory, international migration poses greater barriers to immigrants, and it disrupts social networks more seriously than domestic migration, which may lead to the tendency of international immigrants to have better health. Of the large number of empirical studies that have tested this hypothesis, some have confirmed it
[33][34], and others have only partially confirmed it
[35].
The second hypothesis is the “salmon bias” effect, or selective return migration, which postulates that immigrants experiencing deteriorating health have a greater tendency to return or move to the place of emigration than healthier migrants
[33][34][36]. This hypothesis notes the important influence of health on immigrants’ willingness to settle down. Immigrants who face health problems are limited in their ability to perform efficient work in the local society, which results in a decline in income and living standards. These factors, together with other restrictive factors, such as the lack of social security facilities and social support networks, encourage them to decide to return to their hometowns, or places close to their hometowns, rather than remain in the local society. Ullmann et al. found that immigrants returning to Mexico from the United States had a higher prevalence of chronic diseases than nonimmigrants, such as obesity, lung disease, or heart disease, but there was no difference in the prevalence of other diseases, such as hypertension and diabetes
[37].
Many empirical studies have been conducted to test these two hypotheses. For example, Turra and Elo proposed a method to directly evaluate the salmon bias of immigrants from Spain to the United States, and only limited evidence supported this hypothesis
[33]. In contrast, Sander studied immigrants returning to Turkey from Germany and found that men in poor health were less likely to return than men in good health, which was considered evidence of the decline in the health status of immigrants in the destination
[38]. In China, there are many studies on the domestic floating population that directly or indirectly test the above two hypotheses. For instance, Chen found the existence of the healthy-migrant effect by comparing the floating population and local residents in Beijing
[39]. Tong and Piotrowski found that healthy migrants were more likely to stay in the city, although the relationship between health and migration diminishes across time
[40]. Lu and Qin compared the self-rated health of the returning and the settled floating populations and found that the results supported both the “health migrant” hypothesis and the salmon-bias effect
[31].
Through the analysis of China’s urban–rural mobility data, Xie et al. found that self-evaluated physical and mental health is an important factor that influences the permanent settlement of the floating populations in cities. Moreover, the willingness of the floating population to settle permanently in cities is regulated by the length of their residence
[41]. Early studies also revealed that urban and rural migrants have a higher risk of psychological problems. Migrants with psychological disturbance are more willing to return to their hometowns than to settle down in their immigration destination because the social ties in their hometowns can help to ease their mental tension
[42][43].
3. Health Change, Length of Stay, Insurance Status, and Long-Term Settlement Intention
The studies mentioned above all highlight the close relationship between health and immigrants’ settlement intentions. They mostly looked at the relationship between health and settlement from the results, instead of looking at the relationship between changes in health and settlement from a dynamic process.
From the process point of view, health is not changeless but is constantly changing. Many early immigrants worked in the second labor market, with low wages and poor welfare
[44][45]; however, this did not mean that immigrants could only work in the low-end labor market. In fact, many highly skilled immigrants were still able to obtain high incomes and high welfare in the immigrant-receiving country
[46][47]. Immigrants who arrive at their destinations in poor health at the beginning may not necessarily need to work in the high-intensity manual sector but may engage in mental work in the sectors with relatively low physical demands. They may work well and obtain better income returns and better medical insurance, and thus acquire mainstream social security resources. The good economic conditions and social security level may make them healthier and more willing to settle down in their destination.
In contrast, people who are initially healthy may suffer from physical and mental exhaustion caused by high-intensity labor and constant social competition, which thus results in the deterioration of health
[48]. Moreover, if immigrants suffer repulsion and discrimination in the local society, or even systemic exclusion, the process of integration may not be successful, which will also bring about psychological pressure. This may further cause serious psychological problems
[49][50]. If the costs of poor health outweigh the benefits of migration behavior, then immigrants may return to their hometowns. Thus, changes in health status rather than health itself may affect settlement intentions.