Manuscript Number: PONE-D-25-21410

Title: Regional Disparities in Subjective Wellbeing Across Europe: A Fuzzy Hybrid TOPSIS Approach

The authors acknowledge the editor and reviewers for their comments that improved the paper's presentation. This document outlines our responses to the editor and reviewers’ comments. Our responses are italicized and indicated by a “�” sign.

Editor

28-Nov-2025

Dear,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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Shaonong Dang, PhD

Academic Editor

PLOS ONE

Editor and Reviewer comments

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� Now, the manuscript meets the PLOS ONE's style requirements

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� We have checked the manuscript with a native English speaker.

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“Data openly available in a public repository that issues datasets with DOI doi.org/10.4232/1.13322”

Please clarify whether this [conference proceeding or publication] was peer-reviewed and formally published. If this work was previously peer-reviewed and published, in the cover letter please provide the reason that this work does not constitute dual publication and should be included in the current manuscript.

� We have now specified the availability of that as follows: All data underlying the findings are openly available in the ISSP Data Archive at GESIS – Leibniz Institute for the Social Sciences, with DOI doi.org/10.4232/1.13322, and have not been used to publish any previous analysis overlapping with the present manuscript.

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� Thank you for your comments. We hope that the new version of the manuscript can be accepted for publication.

Additional Editor Comments:

It is an interesting study where authors investigated the regional disparities in Subjective Wellbeing across Europe. The reviewers have raised some concerns, and authors are suggested to address them carefully to further improve the manuscript.

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Reviewer comments

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

________________________________________

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: No

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: the idea of the study is noble and the objectives are interesting, and overall manuscript is fine but the authors need to address cerain issues like providing proper justification behind choosig a method and why ceratin indicators are being used

� Thank you for your comments. We hope that the new version of the manuscript can be accepted for publication.

Reviewer #2: Thank you for the invitation to review manuscript titled “Regional Disparities in Subjective Wellbeing Across Europe: A Fuzzy Hybrid TOPSIS Approach”. I believe that this manuscript is interesting. However, there are areas in which this manuscript must be improved before it would be suitable for publication. The following is a list of points necessary to improve the paper and which justify the decision to Major Revision.

• The introduction is too brief. The paragraph in the data section justifying the countries analysed should be in the introduction. Furthermore, the data is eight years old, so it should be justified that this time lapse is not relevant to the results obtained. For example, by demonstrating that the World Happiness Index between 2017 and 2025 has not changed significantly.

� We thank the reviewer for this comment. The introduction has been expanded accordingly. Firstly, the justification for selecting the seven countries has been added to the Introduction and rewritten to clarify the goal of ensuring broad territorial representation across EU regions. Secondly, we have added a brief explanation to demonstrate that the eight-year gap does not affect the validity of the findings. The World Happiness Report rankings for these countries remained largely stable between 2017 and 2024, indicating no significant changes in relative well-being levels. These additions strengthen the study's contextualisation and justify the data's temporal relevance.

• The Theoretical background section is not up to date; articles from the last five years are not mentioned. It should be expanded with more recent literature on the context of the research.

� We appreciate this helpful observation. In the revised manuscript, the “Brief Theoretical Background” section has been substantially updated and expanded to incorporate literature from the last five years. Specifically, we now discuss:

i. new multidimensional approaches to SWB;

ii. evidence on regional disparities in SWB across Europe;

iii. updated findings on the role of socioeconomic factors, such as age, education, income and wealth.

These additions ensure that the theoretical framework reflects current research and situates our contribution more effectively within the recent literature. All changes are visible in the revised Theoretical Background section.

• The title of Table 1 is incorrect because it does not include the maximum, minimum, mean, and standard deviation statistics. The title should be changed. And for the seven countries, a table with the aforementioned statistics should be included.

� The title of Table 1 has been corrected to reflect its content as “Sample Composition by Country and Socio-Demographic Characteristics” instead of “Descriptive statistics.”

• It is stated that data is available at NUTS2 and NUTS3 levels, but it is not explained whether the mixed granularity affects comparability (e.g. France NUTS3 vs other countries NUTS2). This should be clarified.

� We thank the reviewer for this important observation. In the revised manuscript, we have added an explanation to clarify why the mixed territorial granularity (NUTS2 for most countries and NUTS3 for France) does not affect the comparability of our analysis. Specifically, the Fuzzy-Hybrid TOPSIS indicator relies on the relative distances between defuzzified values, rather than absolute regional size or administrative scale. Consequently, the method independently evaluates each territorial unit, regardless of whether it corresponds to a NUTS2 or NUTS3 region.

• Elasticities are not standard in TOPSIS; it would be advisable to justify the method better or provide more detailed references.

� We appreciate the reviewer’s comment. In the revised manuscript, we have expanded the methodological explanation of the elasticity measure and added supporting references. Although elasticities are not part of the traditional TOPSIS framework, they have been introduced in recent studies to assess the marginal influence of each item on the synthetic indicator. Following Martín & Indelicato (2022) and other applications in fuzzy multi-criteria decision-making (MCDM), elasticities provide an interpretable sensitivity measure that complements the TOPSIS score without altering the method’s core structure. We have clarified this rationale and added detailed references and explanations in the Methodology section.

• Quantile regression is applied to a continuous indicator derived from TOPSIS, but the covariates have potentially relevant correlations (age, education, health, income). A correlation matrix (or at least VIF for multicollinearity) must be included in the text.

� We appreciate this comment. In the revised manuscript, we now include multicollinearity diagnostics to assess the correlations among age, education, health, and other covariates. Specifically, we show that all VIF values fall well below commonly accepted thresholds (maximum VIF = 3.19). This confirms that multicollinearity is not a concern in our quantile regression specification.

• Table 7 should include the Pseudo-R² by quantile

Robustness techniques for estimation must be specified.

� Table A1 has been updated to include the Pseudo-R² values for each estimated quantile (0.25, 0.50 and 0.75).

• The conclusions should not include statements such as: The results agree with other studies (Smith & Diekmann, 2017; Tovar & Bourdeau-Lepage, 2013; Churchill et al., 2019; Cohen, 2002; Steptoe et al., 2015; Thomson et al., 2022; Varela et al., 2021). This should be included in the discussion. The conclusions should highlight the main contribution of the research, its limitations and future lines of research.

� We thank the reviewer for this observation. We have revised the Conc

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