Impact of Migrant Workers on Total Factor Productivity in Chinese Construction Industry

Round 1

Reviewer 1 Report

This paper presents an analysis of the impact of migrant workers on Total Factor Productivity of the Chinese construction industry for the period of 2008-2015. This reviewer reviewed the manuscript carefully and found that the manuscript has a number of major issues as follows:

-        First al, this paper does not provide clear research aim or objective, and thus, it is unclear what the goal of the research really was and what had been actually achieved. In addition, the research motivation needs to be better explained. (Why it was attempted to see the relationship between the migrant worker’s contributions and TFP? What was the research project conceived from the beginning?)  Otherwise, the expected contribution of this work is very unclear.

-        The research design is convoluted and poorly explained. While the research flow diagram in Figure 1 is helpful, much more clear explanation about the whole research flow is required. On the current form of the Methodology section, it is not clear at all how all the variables and scenarios were created/selected and how the comparison of the two scenarios can validate the impact of migrant workers on TFP.  As the details of the scenarios  are critical in this research, much more explanations for them are required.

-        This reviewer found it also difficult to understand why the authors chose only two input factors, fixed assets and number of employees, to calculate TFP. Following the definition of TFP, TFP usually includes all labour and capital inputs to calculate the economic efficiency (i.e., output produced by the total inputs). This reviewer is unsure how well the two inputs factors used in this research can represent all labour and capital inputs used by the whole industry. Much more justification should be provided to support this important component of the present research, in this reviewer’s opinion.

-        Similarly, this reviewer is unsure about the way the inputs of migrant workers are measured. The paper says it had to adopt a complicated process to calculate the number of migrant workers and the salaries of the migrant workers and also used a linear modelling to obtain the number, salary, and work duration for migrant workers. However, all this process was not sufficiently explained or justified, and therefore it is very difficult to evaluate the validity of the methods used.

-        In the discussion section, the careful and in-depth interpretation of the results need to be provided, but instead the whole section introduces further derivation of equations.  Similarly, all the results presented in section 6.2 is unclear as to what they are and how they were produced. It looks like section 6 is whole new research works not directly related to the results presented in the Results section.

-        The overall writing quality and organisation of the manuscript is poor, and as a result the manuscript is very difficult to follow. This reviewer recommends the paper be re-organised comprehensively.

-        Last but not least, authors’ contributions are unclear. Accordingly to the Author Contributions section, Yuhe Wang seems to have been involved with most of the component of the work while others contributing less, but still the person is positioned as a second author. Furthermore, one author did not seem to do anything but listed as a co-author. 

Author Response

We are grateful to the anonymous reviewer for extremely valuable approval and encouragement, which inspires us to move forward on the academic path.

For  careful comments and suggestions, we have basically adopted in the revised submission. In detail, the revised manuscript has a number of major changes to response the found issues as follows:

For the first issue, new version provides clear research aims including 3 objectives in order. Namely the main and first objective is to validate and measure the potential impact of migrant workers on TFP in Chinese construction industry, which would achieve the results of migrant workers’ impact on TFP; the second objective is to explore and reveal the potential impact mechanism, which will obtain the impact mechanism or relations between migrant workers and TFP; the third objective is to discuss and analyze the reasons of such impact by applying the revealed mechanism, which will achieve explain the reasons of the potential migrant workers’ impact on TFP in Chinese construction. The above objectives are reported in introduction section. In addition, the research motivation is presented in introduction as well. In detail, these explanations can be found in lines 62-63, 73-74 and 81-87.

 

For the second issue, on the basis of clearly defining the objectives, we the research flow diagram in Figure 1 is adjusted. Moreover, more explanations for the organization of the revised version are conducted. In detail, stage 1 is the preparatory phase of this work, all variable sections are based on a system literature review in section 2. For the scenario selection, TFP is only measured indirectly through a comparison between inputs and outputs, thus, it is extremely difficult to measure the impact of migrant workers on TFP directly. On the basis of section 1 and 2 (“Introduction and Literature review”), we draw lessons from the common paradigm of experimental design to create Scenario A and Scenario B. In detail, Scenario A without considering migrant workers is seemed as control group, while Scenario B including migrant workers is just experimental group where migrant workers are the only control variable. Hence, the impact of migrant workers on TFP can be expressed throughout a subtraction formula, i.e. the impact of migrant workers on TFP = measurement result in Scenario B - measurement result in Scenario A. These explanations can be found in Figure 1 and section 3.1.

 

Similarly, for the third issue, more detailed explanations and more evidences can be reported in section 2, especially in Table 1. In addition, according to theory of Solow Residual, choosing only two input factors - fixed assets and number of employees, is a common strategy to calculate TFP. Related evidences can be seen in 3.2 section, especially the Eq. (1).

 

For the fourth issue, based on the selected variables and indicators, the data of migrant workers collected are just the number and salaries (these data are mainly used to set up Scenario B). As anonymous reviewer mentioned that we adopted a complicated process to calculate the number of migrant workers and the salaries of the migrant workers, in revised submission we provide some detailed explanations and evidences to prove the validity, but we don't think that's enough. However, in the global context of lack of the data on migrant workers, it might be one of the better options at the moment. Looking to the future, these limitations will be overcome.

 

For the fifth issue, as reported in the anonymous reviewer’s comments, generally speaking, the careful and in-depth interpretation of the results need to be provided in the discussion section. However, in this paper, in results section we achieve the first research aim, namely validate that migrant workers have a significant impact on TFP. Hence, in the following discussion, we mainly focus on what the mechanism of forming such impact is, which contributes to achieve the second research aim of this work. These equations in section 6.1 are just used to explore and deduce the relations between migrant workers and TFP. Similarly, to improve TFP effectively, in section 6.2 we apply the revealed mechanism to analyze the reasons of the above enormous impact in Chinese construction industry, which can help us achieve the third research aim of this work.

 

For the last issue, in original version some important information on authors’ contributions is badly missed, i.g. idea source, supervision and revision draft (reviewing and editing), which leaves authors’ contributions unclear. In revised manuscript authors’ contributions are clearly reported.

 Enclosed please find the revised manuscript "Impact of migrant workers on total factor productivity in Chinese construction industry".

Best wishes!

Reviewer 2 Report

The paper is mostly well-written and presented, and deals with an interesting topic about total factor productivity and critical importance to the construction industry, which is relevant in developing and developed countries. It should be relevant and interesting to the readership of Sustainability.

Author Response

      We are grateful to the anonymous reviewer for extremely valuable approval and encouragement, which  inspires us to move forward on the academic path.

Best wishes!

Reviewer 3 Report

The paper is well prepared. The research design is appropriate, the methods are adequately described, the results are clearly presented. 

The single desirable improvement - to improve the abstract. Please clearly define the aim of the research in the abstract. Also please show direct relations to the topics of sustainability not only in introduction, but also in the abstract.    

Author Response

     We are grateful to the anonymous reviewer for extremely valuable approval and encouragement, which  inspires us to move forward on the academic path.

     For your careful comments and suggestions for the manuscript "Impact of migrant workers on total factor productivity in Chinese construction industry", we have adopted completely in the revised submission.In the new version,we change the abstract to show the direct relations to the topics of sustainability, and clearly define the aim of this work.

Best wishes!

Round 2

Reviewer 1 Report

This reviewer carefully reviewed the revised manuscript and found that the authors did not take his review comments and questions seriously. As the revised manuscript submission with the track-changes clearly show, the revised manuscript, in fact, ended up having only a few sentences changed/added and did not show a substantial improvement at all. As a result, the revised manuscript did not provide any reasons for this reviewer to change his original review comments and recommendation. He is still of the strong opinion that the paper would require a major revision before the manuscript can be re-considered for its publication in the Journal.   

Author Response

We are grateful to the anonymous reviewer for extremely valuable comments again, which will inspires us to perfect the manuscript "Impact of migrant workers on total factor productivity in Chinese construction industry".

For these comments, any revisions to original manuscript are clearly highlighted in red. In detail, the revised manuscript has been completely modified according to the reviewer' suggestion. Finally, the paper has been re-organized comprehensively.

Best wishes!

Round 3

Reviewer 1 Report

This reviewer appreciates the authors' efforts to address this reviewers' comments and questions in this round of revision. However, there are a few issues remaining as follows: 1. As the authors admitted in the manuscript, a large number of assumptions have been used in this research. This reviewer suggests that the authors summarise all the assumptions used in the modelling somewhere in Section 2 or 3 to clarify what has been from real data and from assumptions. 2. This reviewer could not follow why the authors argue that the improvement of migrant workers' quality is obtained through "learning by doing". Without a clear explanation or result directly supporting it, it sounds like a speculation, and this reviewer recommends that the authors review the statement. 3. This reviewer still sees that the discussion section introduces yet another analysis. He recommends that the authors re-organise these sections so that all the analysis results are explained in the result section and the discussion section provides the interpretation of the results and the implications.

Author Response

We are grateful to the anonymous reviewer for extremely valuable approval and encouragement, which inspires us to move forward on perfecting this paper.

For these comments, any revisions to original manuscript are clearly highlighted in red. The revised manuscript has been completely modified according to the reviewers' suggestion. In detail, the revised manuscript has a number of major changes to response the found issues as follows:

   For the first issue, new version summarizes all the assumptions used in the modelling somewhere in the end of Section 3.

   For the second issue, revised manuscript provides a clear explanation on that the improvement of migrant workers' quality is obtained through "learning by doing".

   For the third issue, we re-organize discussion section so that all the analysis results are explained in the result section and the discussion section provides the interpretation of the results and the implications.

On this basis, the conclusion section is slightly revised as well.

Best wishes!

Author Response File: Author Response.pdf