Regional Differences and Convergence of Technical Efficiency in China’s Marine Economy under Carbon Emission Constraints
Round 1
Reviewer 1 Report
This manuscript investigated and evaluated the technical efficiency of marine economy of different coastal provinces in China under carbon emission constraints. The work enriched the database of the knowledge on the development of China's marine economy. Some questions are needed to be verified. I suggest a modification ahead of a publication.
Some major issues are summarized in the following comments:
1 Line 93 please define the term “Efficiency of marine economy” in details, here.
2 Line 98 Please present the numbers about the “increase”.
3 Why not combine Section 1 and 2?
4 Line 147-148 the data from 2006-2016 seems a little bit old. Are the latest data not available?
Minor problems are listed as following , but not limited as these，
1 Line 20 “statistical” suggested to be “reference”;
2 Line 22 “property rights structure” suggested to be “structure of property rights”
3 Line 23 “On a whole” suggested to be “on the whole”;
4 Line 37 “it” suggested to be “she”;
5 Line 49 “in” suggested to be added before “around”;
6 Line 117 “the” suggested to be added before “provinces”;
7 Line 197 Subscript the “2” in “CO2”;
8 Line 170 be careful to the input of the equations;
The manuscript should be carefully proofread by native English speakers. Generally speaking, some work is required before this manuscript is suitable for publication.
Author Response
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Reviewer 2 Report
Authors investigate the technical efficiency of China's marine economy with CO2 emission reductions in target. The topic is interesting and important. However, my main concern is the following. The used variables are clearly non-stationary. Then, the estimation results can be spurious and thus the results are not valid. In order to to have valid estimation results, Authors should use the changes in natural logarithms in their estimations.
Author Response
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Reviewer 3 Report
Dear authors
This study aims to identify the strategies needed to enhance the sustainability of the marine economy in China. Therefore, the technological efficiency of the marine economy in 11 Chinese coastal provinces under carbon dioxide emission constraints between 2006 and 2016 is investigated by stochastic frontier analysis. The results show that the technological level of the marine economy is on the rise, but some regional differences are identified. While technological levels and industrial structure improve technological efficiency, ownership structures, FDI and energy factors exacerbate it. This improvement in technological efficiency converts the concentration tendency of the industrial structure to a dispersal tendency.This study identifies several factors that improve the technological efficiency of the maritime economy.
The study appears to have produced useful results with precise empirical analysis. However, some revisions are required for publication in the journal:
(1)In the conclusion, the limitations of the study and future directions should be discussed.
(2)In 3.1.2 Variable design, the source of each data should be clarified.
(3)There is no space between the text and the citation number, such as "year[22]" on page 3, line 99, or "Farrell(1957)" on line 138. Check the entire manuscript and correct all.
(4)There should be a line space between the text and the figures and tables, e.g. line 256 on page 6 and line 305 on page 7. Check the entire manuscript and make all corrections.
Sincerely.
Author Response
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Round 2
Reviewer 1 Report
thank your for answering my questions.
Author Response
We thank you for your valuable comments to improve the manuscript for the revised version.
Reviewer 2 Report
Unfortunately, Authors still ignore the nonstationarity problem in their data. The problem is well-known and it should take account when a time dimension is present. The problem can be clearly seen when the observations are increased in time. Authors have 11 observations in time with the variance of X. If observations were 22, then the variance (or standard deviation) of the observations would be significantly larger. In fact, when observations approach infinity, the variance of the observations approaches also infinity. This phenomenon is the reason why the estimation results can not be trusted. Thus, I recommend that Authors use the changes of natural logarithm in order to have valid estimation results.
Author Response
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