Morphological Structural Factors Affecting Urban Physical Vulnerability: A Case Study of the Spatial Configuration of Commercial Buildings in Nakhon Si Thammarat, Thailand
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis paper analyzed morphological structural factors affecting urban physical vulnerability, which is innovative, and some minor revisions should be made before acceptance.
1. The methodology section on developing the Physical Vulnerability Index (PVI) could benefit from further clarification, particularly in the application of Principal Component Analysis (PCA). While the use of PCA to reduce data complexity is well-justified, additional details on how each of the 9 variables was weighted in the final index could be included. Specifically, the process for standardizing the variables and how factor rotation was applied to interpret the results could be more explicitly described, ensuring that the readers understand how these steps contributed to the overall PVI.
2. The study defines the unit of analysis as 60 commercial building areas connected to a main road in Nakhon Si Thammarat, Thailand. While this is a well-defined scope, the authors should provide more justification for the selection of this particular study area. For example, why was this specific road and set of commercial buildings chosen over other potential locations in the city? A more detailed explanation of how these buildings are representative of broader urban vulnerabilities would enhance the external validity of the study.
3. The paper focuses on morphological factors influencing physical vulnerability, but external factors like economic activities, local governance, and disaster preparedness plans are not fully explored. These elements could provide a more holistic understanding of urban vulnerability. Including a brief discussion on how these external factors might interact with the physical characteristics analyzed would add depth to the analysis and provide a more comprehensive view of urban resilience.
4. The study highlights the influence of both micro-level and macro-level morphology on physical vulnerability, but it would be useful to expand the discussion of practical implications for urban planning and policy-making. How can these findings be integrated into urban design practices? For instance, should urban planners prioritize improving street connectivity in areas identified as highly vulnerable? A more detailed set of recommendations for policymakers based on the study’s findings could be included to enhance the article’s impact.
5. The authors mention the application of space syntax methods and the limitations of their chosen study area, but they could more explicitly address the limitations of the methodology itself. For example, how might the data collection methods (e.g., manual surveys, Gate Counts) introduce biases? Furthermore, while the study identifies key morphological factors, it would be helpful to discuss potential future research directions, such as exploring the impact of temporal changes (e.g., changes in land use or population density over time) on vulnerability, or applying the PVI in other urban settings to test its generalizability.
Author Response
Comment 1. The methodology section on developing the Physical Vulnerability Index (PVI) could benefit from further clarification, particularly in the application of Principal Component Analysis (PCA). While the use of PCA to reduce data complexity is well-justified, additional details on how each of the 9 variables was weighted in the final index could be included. Specifically, the process for standardizing the variables and how factor rotation was applied to interpret the results could be more explicitly described, ensuring that the readers understand how these steps contributed to the overall PVI.
Response 1: In Section 4.2.1 Variable Standardization, an explanation has been added regarding the objective of the standardization process, which is to transform measurement results with different units into a common scale to facilitate analysis.
In Section 4.2.3 Factor Extraction, further explanation has been provided on the purpose of extracting factors and the rationale for selecting the Principal Components Analysis (PCA) method.
In Section 5.2.2 Factor Extraction, an explanation has been added regarding the principle of considering factor loading values for factor extraction. The importance of each variable within a factor is ranked by the magnitude of its factor loading, which affects the calculation of the Physical Vulnerability Index (PVI).
In Section 5.2.3 Factor Rotation, additional explanation has been included regarding the objective of factor rotation, which is to facilitate the grouping of variables under each factor and improve interpretability. The rationale for selecting the Varimax technique for factor rotation has also been provided.
Below Table 7, further clarification has been added regarding the meaning of factor loading values, which are ordered by their level of importance, and the meaning of the percentage of variance (% of Variance), which indicates the extent to which each factor contributes to physical vulnerability.
Comment 2: The study defines the unit of analysis as 60 commercial building areas connected to a main road in Nakhon Si Thammarat, Thailand. While this is a well-defined scope, the authors should provide more justification for the selection of this particular study area. For example, why was this specific road and set of commercial buildings chosen over other potential locations in the city? A more detailed explanation of how these buildings are representative of broader urban vulnerabilities would enhance the external validity of the study.
Response 2: In Section 3 Research Area, additional justification has been provided for the selection of this particular study area, as follows:
(1) The area is influenced by the spatial morphology of the transportation network, in accordance with Space Syntax theory; and
(2) The study area is exposed to external flood hazards, which means that the physical structure's sensitivity contributes to a higher level of urban vulnerability.
Comment 3: The study defines the unit of analysis as 60 commercial building areas connected to a main road in Nakhon Si Thammarat, Thailand. While this is a well-defined scope, the authors should provide more justification for the selection of this particular study area. Including a brief discussion on how these external factors might interact with the physical characteristics analyzed would add depth to the analysis and provide a more comprehensive view of urban resilience.
Response 3: At the end of Section 6 Discussion, the theoretical discussion has been expanded to explain how exposure to external factors increases urban vulnerability due to the internal physical sensitivity of existing urban systems. Furthermore, the role of adaptive institutions has been emphasized as a key factor in reducing urban vulnerability.
Comment 4: The study highlights the influence of both micro-level and macro-level morphology on physical vulnerability, but it would be useful to expand the discussion of practical implications for urban planning and policy-making. How can these findings be integrated into urban design practices? For instance, should urban planners prioritize improving street connectivity in areas identified as highly vulnerable? A more detailed set of recommendations for policymakers based on the study’s findings could be included to enhance the article’s impact.
Response 4: Section 7 Conclusions, a recommendation has been made to promote collaboration between private-sector real estate developers and public-sector urban planners. This collaboration is proposed as an institutional governance mechanism for overseeing the development of urban physical structures. The aim is to integrate the urban morphological structure across citywide, neighborhood, and community levels into a cohesive system, thereby reducing the physical vulnerability of cities.
Also in Section 7 Conclusions, a policy recommendation has been proposed: the implementation of land readjustment through public-private cooperation. This aims to establish spatial morphological connectivity at both micro and macro levels, particularly in areas with high physical vulnerability. The goal is to reduce dead-end roads, enhance the accessibility of the transportation network, and mitigate the accumulation of negative externalities, which ultimately contribute to increased urban vulnerability.
Comment 5: The authors mention the application of space syntax methods and the limitations of their chosen study area, but they could more explicitly address the limitations of the methodology itself. For example, how might the data collection methods (e.g., manual surveys, Gate Counts) introduce biases? Furthermore, while the study identifies key morphological factors, it would be helpful to discuss potential future research directions, such as exploring the impact of temporal changes (e.g., changes in land use or population density over time) on vulnerability, or applying the PVI in other urban settings to test its generalizability.
Response 5: In Section 4.1.2 Data Collection Methods for Each Variable, a note has been added below Table 2 to clarify the limitations of data collection through field surveys. It is acknowledged that self-administered surveys may introduce bias, potentially leading to data distortion. To minimize such bias, a standardized survey was developed, and data collection was conducted across varied days and times to ensure consistency and broader coverage.
At the end of Section 7 Conclusions, a suggestion for future research has been provided: the study of adaptive institutions, which are considered a key governance mechanism for managing the influence of urban morphological structures on physical vulnerability. This is essential for reducing urban sensitivity and enhancing future urban resilience.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI think that the article is potentially interesting, but it is presently written as if it were still partially a draft and needs substantial editing and adjustment. More specifically, I think that:
(a) It should be clearly specified throughout the text that when morphology is discussed, what is meant is always urban layout morphology, as in the Space Syntax model, and not morphology per se. This issue recurs throughout the manuscript and would require widespread, detailed changes.
(b) The research area section should be moved after the literature review section.
(c) Most importantly, the formula of the Physical Vulnerability Index should be introduced in all its aspects and implications, checked, and commented upon (see also further comments below regarding this).
More specific observations along the text follow.
Line 14–15, "significant changes in urban morphology": This should be better defined. Do you mean a swift departure from an established equilibrium regarding urban shape?
Line 16, "influence": should be infuence → influence (spelling error).
Line 17, "affected by morphological structures": Unclear. Please clarify the intended meaning.
Line 18, "contributed": should be contributes.
Line 19, "the indicator-based": should be an indicator-based.
Line 32, "considered a dynamic pressure": Perhaps rephrase to considered related to a dynamic pressure?
Line 35, "[1-7]": Too many references stacked together. They should be structured, synthesized, or pruned.
Line 36, "...so-called...": The sentence is incomplete.
Line 37–38: See comment above regarding line 14–15.
Line 43: Capital letters should be consistently used for Space Syntax throughout the manuscript.
Line 43–44, "studying the characteristics of urban morphology to maintain the centrality of cities...": This phrasing seems questionable; consider revising for clarity or precision.
Line 48, "movement patterns": Consider completing this with something like ...and street layout integration.
Line 50: Suggest rephrasing to Following the Space Syntax theory,...
Line 55, "while the research question is": Better phrased as by responding to the following research question:
Line 59, "according to the Space Syntax theory": Suggested rephrasing: and analyse them utilizing the Space Syntax theory.
Line 72, "were computed": Perhaps rephrase to showed the existence of?
Line 83: In the Literature Review, most references are established contributions by Hillier himself. It would strengthen the section to include more up-to-date contributions in parallel.
Line 85, "on literature review": Suggested revision: on agreed criteria drawn from the literature.
Line 146–147: These lines should be moved to the beginning of the Methodology section.
Line 155–156, Cutter’s et al. approach: This should be moved into the Methodology section as well.
Line 160, Principal Component Analysis: A reference is needed here, and relevant literature cases using PCA to interpret parametric problems should be mentioned.
Lines 314–316 – super important:
The formula currently written is:
PVIj = Variance_i [(Factor-Loading_i1 × Zscore_1j) + (Factor-Loading_i2 × Zscore_2j) + ... + (Factor-Loading_in × Zscore_nj)] + ... + Variance_n [(Factor-Loading_in × Zscore_nj)].
This formula is referenced as being derived from Tontisirin, Marome, & Anantasuksomsri (2016) [46], which should be explicitly cited in this paper. However, I could not access that reference online and therefore was unable to verify it. Still, the formula as presented raises several concerns. Notably, variance appears only in the first and last terms, and the indices for the term before the last are the same as for the last term, which also includes variance. This inconsistency is troubling.
The authors should double- or triple-check the formula. At a minimum, an explanation is due regarding its derivation. If this is a typing error, that has one set of consequences; if it is the formula as applied, then that is quite different. Of course, it may be correct and I may simply have misunderstood—but clarification is essential.
Line 451, "development": Is this a development or a usage? It seems to be the latter.
Line 458, "The resulting value, known as the 'Physical Vulnerability Score (PVScore)'": Is a new term really necessary here? This seems to be just a normalized version of the Physical Vulnerability Index.
Figures 3, 4, 5, 6: Could these figures be linked more clearly to the map in Fig. 2 using letters, numbers, or other indices?
Line 658, "demonstrates a systematic quantitative measurement at the local scale.": It does not demonstrate a measurement—it uses or adopts one.
Author Response
Comment 1: It should be clearly specified throughout the text that when morphology is discussed, what is meant is always urban layout morphology, as in the Space Syntax model, and not morphology per se. This issue recurs throughout the manuscript and would require widespread, detailed changes.
Response 1: In Section 2 Literature Review, I began by providing a definition of Urban Morphology based on Space Syntax theory. It refers to “the analysis of the forms and morphological structures of communities. It involves studying the spatial relationships (spaces) by using axial lines based on the street network as a representation for examining and analyzing the urban form and morphological network.”
Additionally, this research focuses specifically on urban layout morphology, which refers to “the study of the structural relationships of the city through the layout and connectivity of the transportation network, the utilization of buildings, and open spaces that reflect the visibility of buildings.” This serves as the conceptual framework for this study in analyzing the morphological structural factors that influence the physical vulnerability of urban areas.
Comment 2: The research area section should be moved after the literature review section.
Response 2: I have moved the Research Area section to follow the Literature Review section as recommended.
Comment 3: (c) Most importantly, the formula of the Physical Vulnerability Index should be introduced in all its aspects and implications, checked, and commented upon (see also further comments below regarding this).
Response 3: I have reviewed the formula of the Physical Vulnerability Index and revised the relevant details by explaining the origin, significance, and meaning of each variable used in the calculation. These explanations have been incorporated into Sections 4.2 Principal Component Analysis (PCA), 4.2.1 Variable Standardization, 4.2.3 Factor Extraction, and 4.3 Physical Vulnerability Index (PVI). Additionally, the calculation formula has been adjusted to enhance clarity and improve reader understanding.
Comment 4: More specific observations along the text follow.
Line 14–15, "significant changes in urban morphology": This should be better defined. Do you mean a swift departure from an established equilibrium regarding urban shape?
Response 4: I have revised the sentence to:
“One of the key root causes of urban vulnerability is significant changes in urban layout morphology which significantly influences the determination of accessibility potential, causing some areas to grow while others decline.”
This revision was made to enhance clarity and ensure the meaning is more easily understood.
Comment 5: Line 16, "influence": should be infuence → influence (spelling error).
Response 5: I have made the revisions as recommended.
Comment 6: "affected by morphological structures": Unclear. Please clarify the intended meaning.
Response 6: I have added further clarification as follows:
“…affected by the transformation of urban structure resulting from the layout and connectivity of the transportation network at the global, local, and community levels.”
Comment 7: Line 18, "contributed": should be contributes.
Response 7: I have made the revisions as recommended.
Comment 8: Line 19, "the indicator-based": should be an indicator-based.
Response 8: I have made the revisions as recommended.
Comment 9: Line 32, "considered a dynamic pressure": Perhaps rephrase to considered related to a dynamic pressure?
Response 9: I have revised the text as recommended to:
“Urban vulnerability is considered related to a dynamic pressure stemming from root causes of susceptibility within the urban system.”
Comment 10: Line 35, "[1-7]": Too many references stacked together. They should be structured, synthesized, or pruned.
Response 10: I have revised and reduced the excessive overlapping references.
Comment 11: Line 36, "...so-called...": The sentence is incomplete.
Response 11: I have revised the text as recommended to: “following an approach known as ‘place-based approaches.
Comment 12: Line 37–38: See comment above regarding line 14–15.
Response 12: I have revised the sentence to:
“One of the key root causes of urban vulnerability is significant transformations in urban layout morphology due to transformations in the urban transportation network, which lead to urban decline.”
This revision was made to improve clarity and ensure the meaning is more clearly understood.
Comment 13: Line 43: Capital letters should be consistently used for Space Syntax throughout the manuscript.
Response 13: I have revised the manuscript to consistently use the term Space Syntax throughout.
Comment 14: Line 43–44, "studying the characteristics of urban morphology to maintain the centrality of cities...": This phrasing seems questionable; consider revising for clarity or precision.
Response 14: I have revised the sentence to:
“studying the characteristics of urban layout morphology that influence the growth and decline of urban areas”
This revision was made to improve clarity and ensure the meaning is more clearly understood.
Comment 15: Line 48, "movement patterns": Consider completing this with something like ...and street layout integration.
Response 15: I have made the revisions as recommended.
Comment 16: Line 50: Suggest rephrasing to Following the Space Syntax theory,...
Response 16: I have revised the text as recommended to the Space Syntax theory.
Comment 17:Line 55, "while the research question is": Better phrased as by responding to the following research question:
Response 17: I have revised the text as recommended to:
“…to examine the morphological factors that influence physical vulnerability, responding to the following research question:…”
Comment 18: Line 59, "according to the Space Syntax theory": Suggested rephrasing: and analyse them utilizing the Space Syntax theory.
Response 18: I have revised the text as recommended to:
“…affect spatial vulnerability and analyse them utilizing the Space Syntax theory.”
Comment 19: Line 72, "were computed": Perhaps rephrase to showed the existence of?
Response 19: I have made the revisions as recommended.
Comment 20: Line 85, "on literature review": Suggested revision: on agreed criteria drawn from the literature.
Response 20: I have revised the text as recommended to:
“Grounded on agreed criteria drawn from the literature.”
Comment 21: Line 83: In the Literature Review, most references are established contributions by Hillier himself. It would strengthen the section to include more up-to-date contributions in parallel.
Response 21: In Section 2 Literature Review, I have added more up-to-date references as recommended.
Comment 22: Line 146–147: These lines should be moved to the beginning of the Methodology section.
Response 22: I have made the revisions as recommended.
Comment 23: Line 160, Principal Component Analysis: A reference is needed here, and relevant literature cases using PCA to interpret parametric problems should be mentioned.
Respons 23: I have added the recommended references and provided detailed explanations regarding the origin, significance, and meaning of each variable used in the calculation. These have been included in Sections 4.2 Principal Component Analysis (PCA), 4.2.1 Variable Standardization, and 4.2.3 Factor Extraction, in order to enhance clarity and improve reader understanding.
Comment 24: Lines 314–316 – super important:
The formula currently written is:
PVIj = Variance_i [(Factor-Loading_i1 × Zscore_1j) + (Factor-Loading_i2 × Zscore_2j) + ... + (Factor-Loading_in × Zscore_nj)] + ... + Variance_n [(Factor-Loading_in × Zscore_nj)].
This formula is referenced as being derived from Tontisirin, Marome, & Anantasuksomsri (2016), which should be explicitly cited in this paper. However, I could not access that reference online and therefore was unable to verify it. Still, the formula as presented raises several concerns. Notably, variance appears only in the first and last terms, and the indices for the term before the last are the same as for the last term, which also includes variance. This inconsistency is troubling.
Response 24: I have reviewed the formula of the Physical Vulnerability Index and revised the details by explaining the origin, significance, and meaning of each variable used in the calculation. These explanations have been added to Sections 4.2 Principal Component Analysis (PCA), 4.2.1 Variable Standardization, 4.2.3 Factor Extraction, and 4.3 Physical Vulnerability Index (PVI). Additionally, the calculation formula has been adjusted to improve clarity and enhance reader understanding, as follows:
PVI j = Variance i [(Factor Loading i1 x Zscore 1j) + (Factor Loading i2 x Zscore 2j)
+…+ (Factor Loading in x Zscore nj)]
PVI = PVI j +…+ PVI n
PVI = Physical Vulnerability Index of each unit of analysis
PVI j = Physical Vulnerability Index of each component
Variance = Proportion derived from the percentage of variance of the group of variables or component
Factor loading = Weight of the component or the correlation value between the variable and the component
Z-Score = Standardized score of the variable used in the calculation
i = Index of the group of variables or component arranged based on the analysis
j = Index of the component
n = Final index or total number of components
- I have reviewed the results of the Physical Vulnerability Index (PVI) in relation to the level of physical vulnerability across each spatial unit of analysis. The findings show that the PVI values are consistent with real-world conditions, particularly in areas identified as having high levels of physical vulnerability, which are clearly evident. This serves as a validation of the accuracy of the calculation formula.
- I have also added a reference to the study by Tontisirin, Marome, & Anantasuksomsri (2016) as recommended.
Comment 25: Line 451, "development": Is this a development or a usage? It seems to be the latter.
Response 25: I have revised the text to: Application of the Physical Vulnerability Index (PVI).
Comment 26: Line 458, "The resulting value, known as the 'Physical Vulnerability Score (PVScore)'": Is a new term really necessary here? This seems to be just a normalized version of the Physical Vulnerability Index.
Response 26: I have revised the text by removing the term Physical Vulnerability Score (PVScore) to avoid confusion, and I have added further explanation regarding the interpretation of the Physical Vulnerability Index (PVI).
Comment 27: Figures 3, 4, 5, 6: Could these figures be linked more clearly to the map in Fig. 2 using letters, numbers, or other indices?
Response 27: I have added reference numbers to specific parts of the study area in Figures 3, 4, 5, and 6 to make it easier to clearly link these figures with the map shown in Figure 2, as recommended.
Comment 28: Line 658, "demonstrates a systematic quantitative measurement at the local scale.": It does not demonstrate a measurement—it uses or adopts one.
Response 28: I have made the revisions as recommended.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors delivered on all my requests, and I now think that the article is interesting and publishable in its present form.
