Unsustainable Urban Development Based on Temporary Workers: A Study on the Changes of Immigration in Macau between 1992 and 2019
Round 1
Reviewer 1 Report
This is wonderful research. The arguments are straight forward and very powerful. I think for quantitative research. It has four well-related hypotheses. The data that the authors apply is well supporting the arguments.
The studies of Manao have been expanded in recent years. However, the questions of the interaction between the single industry development （gambling/tourism）and the rapid growth of temporary migrant workers in a small island have not been better interpreted. The contribution of this paper is that it analyses the crucial impact of land expansion on the economic diversity and migration model, their interaction, and their dynamic processes. I also believe that all the literature has well fixed the arguments and the discussions.
If I remember correctly, maybe it will be better if you can keep the terms consistently, Macau or Macao.
Author Response
Point 1: The contribution of this paper is that it analyses the crucial impact of land expansion on the economic diversity and migration model, their interaction, and their dynamic processes. It will be better if you can keep the terms consistently, Macau or Macao.
Response 1: We are extremely grateful for the compliment of the Reviewer. We are also grateful for the careful reading of the Reviewer. We have revised all “Macao” in the main body of our paper to “Macau” to keep the terms consistent.
Reviewer 2 Report
This study used the Error Correction representation of the Autoregressive Distributed Lag model 12 (ARDL-ECM) to analyze the impact of urban development on the trends of immigration and labor 13 migration in Macau between 1992 to 2019. The topic is very interesting, but the authors should address the following three concerns before moving to the publication.
1)In the research hypothesis section, what is the logic of the four hypotheses? in line 230, the authors said that "A vicious circle might lie within Macau’s urban development process....." So from the four hypotheses, I cannot the authors establish the relationship between the number of migrant workers and immigrants as well as urban development. Please clarify, and establish the clear analytical framework.
2)The discussion and conclusion of the research should be broadened and generalized, to gather more precise planning principles and policy guidelines for creating Macau's urban development.
3) It is suggested to increase the conclusion section focusing on the possible future development of the research.
Author Response
Point 1: Please clarify, and establish the clear analytical framework.
Response 1: We are extremely grateful for the constructive comment from the Reviewer. We added a variable diagram at the end of the hypothesis section and also explanation on how we develop our hypotheses:
“As is shown in Figure 1, we hypothesize that along with the urban development of Macau, which is featured by increasing land through sea reclamation and rising wage level, the number of migrant workers would keep increasing, while the number of immigrants would keep decreasing. While we are not directly examine the relationship between the amount of migrant workers and immigrants, we would assume that Macau’s reliance on migrant workers is a main driving force of reducing quotas for immigrants. Employers in Macau can now avoid high employee welfare for locals and immigrants and fulfill their demand for laborer through hiring more obedient migrant workers [11]. But as we will discuss more specifically in latter sections, this strategy is not a solution to Macau’s problem of insufficient manpower, but only postpones yet deteriorates its consequences.”
Due to the confusion caused by the discussion on “a vicious circle” within Macau’s development, we now moved that paragraph to the finding section where it fits better.
Point 2: The discussion and conclusion of the research should be broadened and generalized, to gather more precise planning principles and policy guidelines for creating Macau's urban development.
Response 2: We thank the Reviewer for this great suggestion. We have substantially revised discussion and conclusion section. In particular, we expanded three brief arguments in the discussion section into three paragraphs, adding theoretical references and details on the characteristics of Macau’s urban development. We also refined the conclusion section to make our suggestions more precise and straightforward.
Point 3: It is suggested to increase the conclusion section focusing on the possible future development of the research.
Response 3: We totally agree with the Reviewer that suggestions for future development of the research should be presented. We moved introduction on limitations of our study to conclusion section, based on which we offer suggestions for future studies on the migration in Macau and in the Pearl River bay area:
“Covid-19 and subsequent sudden changes have had a significant impact on the long-term patterns of immigration in Macau, ... Thus, further study on the influential factors on Macau’s trend of immigration during and after the pandemic is essential.
We also notice that regional factors have yet to be taken into account in the causal analysis of migration flow in Macau. We expect in the future, there will be studies combining data from Macau, Hong Kong and mainland cities in the Pearl River Delta and present a more comprehensive picture of migration in this bay area.”
Reviewer 3 Report
Very interesting. Elaborate methodology and interesting references. Attention with:
1. A Reflection on the limitations of the ECM model. Which are?
2. The Limitations of census data. reflection on this.
3. The discussion should be more precise and more specific based on the bibliographical references. It would be interesting to introduce some regard to local urban and demographic planning policies (with bibliographic references).
4. How do you see climate change and sea level rise in Macao? Relationship with the United Nations' sustainable development goals?
5. Explain why they do not use statistical indicators on social welfare, housing problems, population density, and social inequality in Macau. And how they could introduce them in their subsequent investigations.
6. The conclusions must be clear, direct, and precise.
Author Response
Point 1: Present the limitations of the ECM model.
Response 1: We thank the Reviewer for this suggestion. We added a paragraph in Methodology section to discuss the limitations of the ARDL-ECM method:
“ECM suffers from several limitations. Specifically, the biggest one is that it requires that the variables are cointegrated. Otherwise, the disequilibrium error term will not be a stationary variable. In other words, the errors in the long-run relationship become larger and larger. Besides, in terms of model specifications, ECM can be explained as a reparameterization of the general ARDL or dynamic linear regression (DLR) models because it focuses on the importance of general to specific modelling (Mizon, 1977). Although the ARDL-ECM imposes no restrictions on the DLR, there are no statistical criteria to distinguish between the two model specifications because they are observationally equivalent. Hence, the interpretation for these coefficients of the ECM is heavily dependent on explicit theory (Alogoskoufis and Smith, 1991). ”
Point 2: Present the limitations of census data.
Response 2: We really appreciate this suggestion. We added a brief discussion on the limitations of using census data. We also introduced our future research plan based on such limitations:
“Moreover, censuses often sacrifice survey comprehensiveness for coverage and Macau’s census didn’t include information on locals’ higher education majors. In fact, high-skilled migrant workers are often technicians or administrators with professional training, while a large proportion of Macau’s university graduates majored in service and literature & art [45]. Surveys and interviews on immigrants and migrant workers in Macau in the future would allow for deepened exploration of the changing mechanism.”
Point 3: The discussion should be more precise and more specific based on the bibliographical references.
Response 3: We thank the Reviewer for this great suggestion. We have substantially revised Discussion section. In particular, we expanded our brief statement on “immigration and population structure”, “small economies relying on tourism” and “relationship between migration and land” in the discussion section into three paragraphs, adding theoretical references and details on the implications from Macau’s case.
Point 4: How do you see climate change and sea level rise in Macao? Relationship with the United Nations' sustainable development goals?
Response 4: We thank the Reviewer for pointing this issue out. Indeed, one major problem related to Macau’s development mode is environmental unfriendliness. We included the following statements in the discussion section:
“Macau on the contrary, makes more use of man-made landscapes, offering tourism, entertainment and consumption activities inside grand casino hotels. Among them, the Venetian Resort Hotel is the largest one, occupying an area of 0.975 km2, that is, 3% out of Macau's total land [44]. The advantage of Macau's economic mode lies in its relatively low dependence on natural landscape, while its disadvantage is the ignorance of the natural environment. Macau's land reclamation has aggravated multiple environmental problems, such as inland sea pollution, coastal ecosystem degradation, flood resistance degradation, soil salinity increase, natural landscape destruction, and heat island effect [8]. Therefore, in addition to the unsustainable population growth and the unstable economic development [67,68], Macau's economic pattern is also environmentally unfriendly and thus conflicts with many United Nations Sustainable Development Goals.”
Point 5: Explain why they do not use statistical indicators on social welfare, housing problems, population density, and social inequality in Macau, and how they could introduce them in their subsequent investigations.
Response 5: We thank the Reviewer for pointing this issue out, and we totally agree that social welfare, housing price, housing area and population density are also potentially influential indicators for migration in Macau. In fact, we have tried to add them in the model during the process of model construction, but due to the constraints of the autoregressive lag model and our data from yearbooks, the inclusion of these indicators is often detrimental to the model fitting.
We do plan to further explore the impact of these factors when we collect individual data in the future. We do notice that temporary workers in Macao are facing multidimensional and complex social inequality problems. We will collect information on the subjective feelings of workers in the future through surveys and combine them with objective data to construct a better index on laborforce inequality in Macau. We agree that such refinement can help deepen the understanding of the mechanism. We added a note (footnote No. 2) in data section to address this issue.
Point 6: The conclusions must be clear, direct, and precise.
Response 6: We can’t agree more with this comment. We have refined and restructure our conclusion section, which help make our arguments more straightforward: “We find that two important indicators of Macau's urban development, its land area and wage level, both have positively long-term influence on the number of migrant workers.” “Our study also shows that the above two indicators, land area and wage level, have negatively long-term impact on the number of immigrants. ” “This study reveals one critical problem of Macau's current development strategy, that after allocating most of the new land reclaimed from the sea to the gaming-tourism industry, the city fails to reserve sufficient land resources for increase of economic diversification or improvement of living environment.”
Reviewer 4 Report
Dear Authors,
The article is interesting and based on the authors' research. It also takes on one of the most important world problems in a large metropolis. Hence, it is worth proceeding further. I have a few comments that I think should improve the article. Especially in the context of the internationalization of content impact.
1. I recommend deepening the review of research on migration related to temporary employment in other countries and large metropolises of the world. This is a global problem. This is what one of the subsections of Chapter 2 should be devoted to. Subsection 2.3 fits rather the Findings chapter.
2. The Discussion chapter is very short and shallowly embedded in the world discourse. This is a very crucial chapter and should be an important asset of the article.
3. My comments on the Background and Discussion section also result from a very limited list of publications that form the background of the article. I believe that this background should be significantly deepened.
Sincerely
Author Response
Point 1: I recommend deepening the review of research on migration related to temporary employment in other countries and large metropolises of the world. Subsection 2.3 fits rather the Findings chapter.
Respond 1: We are extremely grateful for the constructive comment from the Reviewer. We totally agree that adding a subsection on temporary employment in other countries and regions would help build linkage between our study with a broader research field. We added a subsection “2.1. Immigrants & Migrant Workers” to review prior studies on migration in other parts of the world.
We moved the last paragraph in the original subsection 2.3 to the to Finding section where it better fits. We replaced it with a figure and a brief explanation on the general relationship between our research hypotheses.
Point 2: The Discussion chapter is very short and shallowly embedded in the world discourse.
Respond 2: We thank the Reviewer for this suggestion. We have substantially revised Discussion section. Specifically, we expanded our brief statement on “immigration and population structure”, “small economies relying on tourism” and “relationship between migration and land” in the Discussion section into three paragraphs, adding theoretical references and linking the implications from Macau’s case with studies in other regions in the world.
Point 3: My comments on the Background and Discussion section also result from a very limited list of publications that form the background of the article. I believe that this background should be significantly deepened.
Respond 3: We totally agree with the Reviewer that a deepened background can lead to increased content impact of our study. We have added 20 new references in the Background section and 7 new references in the Discussion section. The topic of these publications range from general theory of migration to specific research on situation and policies on migration in certain countries and regions.
Round 2
Reviewer 3 Report
Clearer and more focused text. Thank you very much for the notes. I encourage you to continue investigating based on the limitations found.
Author Response
Response: We are extremely grateful for the encouragement from the Reviewer. We have collection existing data on Macau, Hong Kong and other cities in the Pearl River Delta and are at the stage of designing our own survey. We do hope to conduct a more comprehensive examination on the migration issue based on the limitations of our current study.
Reviewer 4 Report
Dear Authors.
The article has been improved in the new version. Nevertheless, I have one more comment on the Discussions and Conclusions. Well, a large part of the Conclusions is in fact part of the Discussion. There should, in principle, no longer be citations or polemics in the Conclusions. I recommend moving the part pasted below to the Discussion.
Sincerely
Based on the annual data from Macau Statistics and Census Service, this study ana- 567
lyzes the influencing factors of the trend of immigration in Macau between 1992 and 2019. 568
Through analysis using ARDL-ECM, we find that two important indicators of Macau's 569
urban development, its land area and wage level, both have positively long-term influence 570
on the number of migrant workers. Macau has regarded temporary migrant workers as 571
an important solution to its scarcity of land and social resources. Migrant workers are only 572
allowed to work in Macau for a few years, so they can flexibly fill vacancies in the labor 573
market without causing long-term pressure on the city's welfare and social resources [38]. 574
Moreover, a large number of migrant workers from Chinese mainland have become cross- 575
boarder commuters, who work in Macau but reside in neighboring cities like Zhuhai or 576
Zhongshan, sparing the scarce housing resources for residents in Macau [68]. 577.
Our study also shows that the above two indicators, land area and wage level, have 578 negatively long-term impact on the number of immigrants. This finding implies that Ma- 579 cau has been suppressing the chance for these migrant workers to become residents dur- 580 ing its urban development process. Although a large proportion of migrant workers are 581 young and highly educated, they are not able to settle in Macau due to restriction of the 582 immigration policy [10]. Unlike earlier immigrants who improved the population struc- 583 ture of Macau and alleviated aging, low fertility and other demographic problems [11], 584 migrant workers' contributions to Macau are relatively short-term. In fact, findings of this 585 study imply that under Macau's current migration policy, increase in the number of mi- 586 grant workers would result in a negative impact on sustainable population development. 587 Consistent with prior studies [6], this study reveals a critical problem of Macau's cur- 588 rent development strategy, that after allocating most of the new land reclaimed from the 589 sea to the gaming-tourism industry, the city fails to reserve sufficient land resources for 590 increase of economic diversification or improvement of living environment. The booming 591 gaming-tourism industry not only affects Macau's attractiveness to non-local talents, but 592 its high-salary and low-skill-requirement positions reserved for local residents also drives 593 local students to concentrate on majors related to gambling, resulting in extremely high 594 homogeneity of local manpower [45]. Macau's GDP plunged by more than half and gross 595 income of gaming industry dropped by 79.2% in 2020 due to Covid-19 pandemic, clearly 596 showing the vulnerability of an economic system solely based on gaming-tourism [69]. 597 Meanwhile, the neighboring mainland cities in Pearl River Delta have significantly in- 598 creased the welfare for non-local talents in recent years in order to compete for human 599 resources [55,70]. Therefore, Macau has become relatively less attractive to the non-local 600 manpower that it relies on and its strategy of rotating high-end workers has become 601 harder to sustain. Therefore, it's the high time for Macau to improve its immigration pol- 602 icies and increase opportunities for skilled migrant workers to gain residency, so as to 603 attract non-local talents essential for its economy.
Author Response
Response: We are extremely grateful for the constructive comment from the Reviewer. We have now moved the parts suggested by the Reviewer from the Conclusion section to the Discussion section. We also adjusted the rest of our Conclusion section and removed citations in this section.
