Review Reports

Round 1

Reviewer 1 Report

I congratulate the author(s) for the work done. It seems to me a relevant, current and necessary work. However, for its better visibility and readability, I would like to make some recommendations:
- It would be good to expand the keywords, if possible, and introduce some more specific ones, in addition to those already present, so that the article is easily traceable in databases. 
- The Introduction seems directly like a theoretical framework, with classic authors known to the scientific community. The problem has to be explained, how it has been detected, why it is being studied and how this article, by doing so, is going to innovate research in the area. 
- The list of results is excellent, congratulations!
- To make the text more readable and presentable in other papers it would be highly recommended to visually summarise the findings in one or two images, some kind of diagram. 
- There are not enough limitations found in the research and no clear prospects for the scientific community: why this work is a breakthrough in its field and how it can be replicated by other researchers. Only a couple of sentences are devoted to this point, when it should be the most relevant when dealing with a topic like this.
- The first time an acronym appears, it would be good if the words that make up the acronym had the first capital letter.
- A harmonious distribution of paragraphs should be sought, so that they all have a similar length, 5-6 lines, with neither very long paragraphs nor very short ones. This will make the text more readable and understandable even if it is already very well written, especially in the theoretical framework or state of the question.
- Pay attention to typos, double blanks and line breaks (in Materials and Methods).
- Check whether Mexico, being in English, should have accents or not, as there are no words with accents in the rest of the paper.

Author Response

Since there are just a few changes that has been well detailed in the attached file, I am uploading the paper without tracking changes. To me, is very confusing to use this option, especially when line breaks or double blanks has to be corrected. I hope it is not a big inconvenience for you.

Thank you for all your recomendations. There were very encouraging to improve my work.

Author Response File: Author Response.pdf

Reviewer 2 Report

A very well conducted study. Particularly compelling was the introduction of the concept of "measuring unsustainability or non-sustainability". 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

After reading the manuscript “Urban sustainability: An alternative roadmap for cities”, I highlight next remarks:

• The organization of the study is highly confusing since theoretical and methodological arguments were combined in several sections without a clear thread. Abundant descriptive and surplus information was provided with scarce value in i.e. Sections 1 and 2.
• Research aim is ambiguous along with the title of the article. Background to support the development of the study should be significantly enhanced. In this sense, the concept of “unsustainability” and its assessment should be also determined.
• An general overview of the methodology proposed should be displayed in Section 2 to enable a potential replication by other scholars. Selection of indicators, normalization, aggregation and threshold values should be thus considered as the main methodological stages. Instead Table 2 comprising metrics, subdimensions, dimensions, weights and sustainability target values was given without any sound rationale.
• Three overly generic criterion served to identify 50 cities, but a large number of cities worldwide also meet those requirements. The purpose, definition, rationale and characterization of the Urban Non-Sustainability Index (UNSI) are very vague. Actually, why is UNSI necessary? UNSI ranges from 0 to 1 without a clear connection between values and non-sustainability performance in cities.
• What is the ? parameter? What are the theoretical bases to use this parameter to compensate sustainability dimensions? What is the purpose of robustness test? It is very controversial the need of that test to build composite indicators as reflected in literature.
• Figures 2 to 5 lack numbers and threshold values to interpret the charts displayed. Please show suitable performance values for urban areas to benchmark the cities reviewed.
• Theoretical and/or practical implications of the research in the field of urban sustainability were not revealed.

As stated above, serious theoretical and methodological flaws were found in the study which should be properly addressed to recommend it for publication.

 

 

Author Response

The authors would like to thank you for your comments. After carefully reading each of your observations, we have substantially changed the presentation of the article, as well as the justification and explanation of the formal aspects. We think that thanks to your valuable contributions, it may be recommended by you for publication.

Author Response File: Author Response.pdf

Reviewer 2 Report

I congratulate the author(s) for the work done. It seems to me a relevant, current and necessary work. However, for better visibility and readability, I would like to make some recommendations:
- The title should be striking, but representative of what is found in the article. It is the first contact with any international researcher and it is necessary to say what the article is about, where it comes from, why it is original. Whatever you can. The current title is too general and I would recommend broadening it and making it more specific, as far as the journal's rules on the length of the title allow. 
- The abstract should be representative of the whole article. It is often the tool that works in search engines and gets researchers to the text. Right now it is too focused on methodology and leaves out why there is a problem to investigate and why there is an original advance in knowledge. It is necessary to make a concrete summary, with all the sections of the work: introduction, objectives, methodology, results, conclusion and prospects (as much as possible in the space allowed by the journal). 
- The introduction should directly resemble a theoretical framework, with classic authors known to the scientific community. It is necessary to explain the problem, how it has been detected, why it is being studied and how this article, by doing so, will innovate research in the area. 
- In a journal of this prestige, the methodology section should include more references, more citations of previous works that have inspired this methodology. 
- There are not enough limitations found in the research and no clear prospects for the scientific community: why this work represents a breakthrough in its field and how it can be replicated by other researchers. Only a couple of sentences are devoted to this point, when it should be the most relevant when dealing with a topic like this.
- A harmonious distribution of paragraphs should be sought, that they all have a similar length, 5-6 lines, with neither very long paragraphs, nor very short paragraphs. This will make the text more readable and understandable, even if it is already very well written. 
- Attention should be paid to typos, double whites and line breaks. 

Author Response

The authors would like to thank you for your comments. It is very motivating that, from the first reading, you have considered that it is a relevant and necessary work. We have adjusted as much as possible to each of your recommendations because we believe that they are very valuable.
Thus, we think that our article has been improved substantially and we hope that it can be recommended by you for its publication.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

After reading the revision of the manuscript “Urban sustainability deficits: The Urban Non-Sustainability Index (UNSI) as a tool for Urban Policy”, I highlight next remarks, most of them already mentioned in the previous report but still unaddressed:

• Because there are multiple frameworks and tools to assess sustainability, the strong argument “If measuring sustainability is “measuring the immeasurable” in line 11 is not acceptable. If so, the appraisal of unsustainability defined by authors as “the distance to a sustainability target” would make no sense.
• Beyond the vague description of unsustainability provided “we define unsustainability for each of the said indicators as the values that are not above a certain threshold”, the concept should be fully characterized.
• Background to support the analysis of “unsustainability” must be strengthened since most Section 1 is focused on general arguments related to sustainability. In this vein, the correlation between UNSI and Urban Policy was not determined. The New Urban Agenda is the adaptation of the 2030 Agenda to the urban realm without any strong implication in the development of urban policies.
• An general overview of the methodology proposed should be displayed in Section 2 to enable a potential replication by other scholars. Selection of indicators, normalization, aggregation and threshold values should be thus considered as the main methodological stages. Instead Table 2 comprising metrics, subdimensions, dimensions, weights and sustainability target values was given without any sound rationale.
• The purpose, definition, rationale and characterization of the Urban Non-Sustainability Index (UNSI) are very vague. Actually, why is UNSI necessary? UNSI ranges from 0 to 1 without a clear connection between values and non-sustainability performance in cities.
• Since ? parameter was depicted as “a parameter to obtain different profiles of compensation”, ? could be deemed as a distorting factor that can alter values of UNSI.
• What are the theoretical bases to use this parameter to compensate sustainability dimensions? What is the purpose of robustness test? It is very controversial the need of that test to build composite indicators as reflected in literature.
• Figures 2 to 5 lack numbers and threshold values to interpret the charts displayed. Please show suitable performance values for urban areas to benchmark the cities reviewed.
• Theoretical and/or practical implications of the research in the field of urban sustainability were not revealed.
• Check reference [58].

The article still presents serious theoretical and methodological flaws. For instance, unsustainability notion was not defined whilst most of the study turns about the statistical analysis of ? parameter. However, the linkage between results and urban sustainability/unsustainability and urban policy is scarce.