An Outlier Detection Study of Ozone in Kolkata India by the Classical Statistics, Statistical Process Control and Functional Data Analysis
Round 1
Reviewer 1 Report
Review
The manuscript is about An Outlier Detection Study of Air Quality in Kolkata India by the Classical statistics, Statistical Process Control and Functional Data Analysis. Some comments are reported below:
· Please add recent references in the introduction section, see these documents as example:
o https://www.mdpi.com/2073-4433/13/4/506
o https://www.mdpi.com/2076-3298/10/3/42
· The introduction section is too long, please summarize the general concepts and make it clear.
· Use the units properly in the paper (μg/m3)
· When you say “especially in 193 developing countries” add references supporting your idea.
· Take out the colon at the end of each title or subtitle.
· Update the references In the “imputation” section
· Please mention all the equations, figures and tables in the text before each of the equations, figures and tables.
· Optimize the space in Table 1
· In figure 2 units are missing
· Please uniform the style of the figures
· Avoid the use of “we” in the paper. Use indirect sentences.
· Start the conclusions section remarking on the objective of the paper.
· Expand the conclusion section and highlight recommendations for future investigations.
Some minor mistakes are detected
Author Response
Dear Reviewer,
We thank you for your time and efforts on our manuscript.
Further, we take this opportunity to thank you for your valuable suggestions. The suggested revisions have been efficiently carried out in the revised version of manuscript.
Thank you.
On the behalf of all authors,
Zhao Xu
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Outliers are observations that differ substantially from the rest of the data and can be detected by comparing the values in question with all the other values. The detection of the outliers plays an important role in finding the source of pollution, improving the consistency of long-term air quality dataset and subsequent analysis. In this sense, this investigation is interesting as it aims to improve our understanding of the air quality in Kolkata Indian via the detection of outliers of air pollutant observations using several mathematical approaches. However, significant deficiencies exist in the manuscript, which are summarized as follows.
1) Too detailed description of the several mathematical approaches is involved in Section 2. (Line 191-Line 406), and most of these methods were elucidated in the previous studies such as Sancho et al. (2014), Di Blasi et al. (2013), etc. Whereas, only a few illustrations about this work are presented in Section 3 and Section 4 (Line 407-Line 490), and few valuable findings, suggestions, and comments are demonstrated in the manuscript.
2) The title of this manuscript indicates that the main content of this study is to detect the outlier of air quality, while only O3 is mentioned in Section 3. It is well known that both O3 and other pollutants (e.g., NO2, CO) have a remarkable influence on air quality. Thus, the research contents of this study do not match its title.
3) Many references are not correctly cited in this manuscript, which have been marked in the review version of the manuscript.
Comments for author File: Comments.pdf
The writing is needed to improve so that it can be understood easily.
Author Response
Dear Reviewer,
We thank you for your time and efforts on our manuscript.
Further, we take this opportunity to thank you for your valuable suggestions. The suggested revisions have been efficiently carried out in the revised version of manuscript.
Thank you.
On the behalf of all authors,
Zhao Xu
Author Response File: Author Response.pdf
Reviewer 3 Report
Respected Author
It is requested to revise the manuscript as suggested.
Regards
Comments for author File: Comments.pdf
Respected Editor
I hope you are doing very well. This article is not acceptable in its present form. If authors are agree to revise and resubmit the manuscript to jounal, then consider the article for acceptance. It is requested to ensure the incorporated major revisions suggested in review process.
Regards
Dr. Shamyla Nawazish
Associate Professor
Department of Environmental Sciences
CUI, Abbottabad Campus
Author Response
Dear Reviewer,
We thank you for your time and efforts on our manuscript.
Further, we take this opportunity to thank you for your valuable suggestions. The suggested revisions have been efficiently carried out in the revised version of manuscript.
Thank you.
On the behalf of all authors,
Zhao Xu
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The revision of the manuscript is improved to some extent compared to the original one, but I still suggest the authors to further enrich the "Results" part and present some valuable investigations.
The English writting in the revised version is improved.
Author Response
Dear Reviewer,
We thank you for your time and efforts on our manuscript.
Further, we take this opportunity to thank you for your valuable suggestions. The suggested revisions have been efficiently carried out in the revised version of manuscript.
Thank you.
On the behalf of all authors,
Zhao Xu
The paper entitled " An Outlier Detection Study of Ozone in Kolkata India by the Classical statistics, Statistical Process Control and Functional Data Analysis" are revised based the comments and suggestions.
Comments and Suggestion for authors:
The revision of the manuscript is improved to some extent compared to the original one, but I still suggest the authors to further enrich the “Results” part and present some valuable investigations.
Response: We improved the results and highlighted with green in the revised manuscript.
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript is revised and significant improvemnent has been observed.
Regards
Comments for author File: Comments.pdf
Author Response
Dear Reviewer,
We thank you for your time and efforts on our manuscript and providing the opportunity to revise the manuscript with your valuable suggestions.
Thank you.
On the behalf of all authors,
Zhao Xu
Author Response File: Author Response.pdf
