Air Pollution and Mobility, What Carries COVID-19?
Round 1
Reviewer 1 Report
Dear Authors
My scientific interests are also related to the spread of the COVID-19 pandemic caused by SARS-CoV-2. Therefore, I am very happy that I could read your very interesting article on this topic.
The manuscript entitled “Air pollution and mobility, what carries COVID-19?” is well-written and has a research and analytic character. The Authors should be appreciated for the research reliability and methods used. The strong points of this article are also its layout and the clarity of presented contents.
The Introduction section, in my opinion, should contain a clearly stated aim and hypotheses that the authors should verify in the course of their analyses. What does the statement "We use panel data with cross-sectional dependence models (...)" mean? What panel data do the authors mean? This needs to be explained to the readers.
The authors omit the "Literature review" section. It would be worth introducing it, in order to show readers what has already been researched in the topic discussed by the authors.
The Materials and methods section should be expanded. It is necessary to explain to the readers in more detail what data the authors used for the analysis and what analytical methods were used by them. In my opinion, the text of the article should be more accessible to a wider group of people, not only econometricians and statisticians.
Results and Discussion sections should be presented separately. The discussion not only consists of describing and commenting on the obtained results but also relating them to the research of other authors on a similar topic. COVID-19 issues are a topic currently being taken up by many researchers around the world.
The Authors believe that their research enriches the subject literature and is important to government and local governments and carry many political implications. I agree with it. But what are the implications of their research for the inhabitants of large agglomerations and areas with high population density? I miss such information.
Researchers do not recognize the limitations of their research. They do not write about them in the Conclusions section and in any other section. It has to be added. The consciousness of the limitations of research proves the high reliability and scientific maturity of the Authors.
I hope that the indicated remarks will help the Authors to improve their text so that the work will be published. Good luck!
Author Response
Please see the attached file.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The topic is outstandingly topical and offer potential policy implementation. The paper is scientific level, but there are places for improvements.
In the abstract the general message that authors send to the readers, other researchers are missing.
The introduction is mixed. I suggest to follow the usual structure of scientific papers, Literature review following the introduction. At the end of introduction please explain the structure of paper.
At the end of the Literature review part, I miss a formulation of research hypotheses that would be connected with the previously published studies and also give information about the potential value added of paper.
The paper claimed that to used Data panel approach. I know that there are some classical assumptions for this method. For instance :
- Normality of dependent variable
- Unit root test for stationary
- Multicollinearity with VIF
- Test of variance equity
I can not see these parts in your paper, however it is also required in general but especially at this high ranking journal of Econometrics, focusing on using of methodology.
Specially, multicollinearity must be mentioned.
Another important note, you mentioned that “We consider a panel data with cross-sectional dependence approach “. The question is :
- How you fix the heteroscedasticity problem through cross-section dependence approach?
Finally, I think that Actual, Fitted, Residual Graph can mention.
The results and discussion part can be be extended. The limitation of research and the future research direction would be useful at the end of conclusion part.
Author Response
Please see the attached file.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors have made significant efforts toimprove the article. I am glad that my suggestions
were considered positive and to be followed.
In its current state, the article is of a high standard,
I recommend its publication.
