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PONE-D-23-15713Squeezed from above: Sociopolitical dynamics in Chile (1938-2019) and its relationship with the process of overproduction of the elites.PLOS ONE

Dear Dr. Muñoz-Rodríguez,

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.

==============================

First evaluator

This paper presents an interesting application of Structural Demographic Theory (SDT) to the case of Chile in the last century. It mostly draws on Goldstone and Turchin’s work, but it seems to go a bit further in terms of methodology by incorporating predictive analytics. The model used achieves to predict social unrest periods, leading the authors to argue that it shows the “underlying cause of Chilean political instability”. Although I think this is a very interesting piece of work, I believe it would benefit from some changes that I would suggest hereafter:

First, I will address some form issues.

I recommend modifying the title of the article to explicitly indicate that it is an application of SDT. That way it would be easier to identify the paper as a part of a broader literature, and would make it more accessible to a wider audience beyond those specifically interested in the Chilean case. Second, I suggest moving the materials and methods section before Results. Such order is common among PLOS articles and it would make a lot easier to understand the results section. Lastly, it appears that there are some issues with the equations when exporting from the text editor (see lines 73 and 348) and some equations seem to have errors (I’m guessing in eq 1 frequency and total occurrence are indexed in i).

Introduction:

This section seems very clear to me. It frames adequately SDT as an “interpretative framework” that “does not seek to encompass all the complexity” behind political instability but is sufficient to model (and predict) social unrest periods. In terms of the explanation of the Chilean case, it is weird that it goes into detail about social unrest during 2019, but does not address other important political instability events during the time window studied. It seems important to provide contextual information on political instability throughout the 20th century in Chile, as the study later treats at least two other events with the same level of importance as the "social outbreak" of 2019.

Results:

Once the goal of the study is introduced, the paper jumps to the results section with a visual inspection of four time series, one for each independent variable and one for an index that aggregates them with a multiplicative model. The visual inspection closes with a big conclusion: “it can be seen how the structural demographic theory predicts an increase in political tension in the Chilean social system prior to the outbreak of the main events of social instability of the last 80 years”. This is one of the main reasons why I recommend putting the methods section before. As I read this without knowing the methods that were going to be used to test predictability, it was easy to conclude the study was flawed. Visual inspection does not support predictability. I suggest either removing this initial part of the results or moderating the conclusion.

Then, the outcome of the model is presented. The authors introduce the Observed Political Instability Index (OPII) and while it can be inferred that this measure represents the dependent variable created by the authors, it would be a lot clearer if the methods section were before the results.

Finally, prediction models are presented: a non-linear regression proves that SDT can fit OPII, Arima model shows a temporal correlation between changes in observed and estimated outcomes, and forecasting provides evidence that SDT can predict the OPII using information from a year before. Unfortunately, this core aspect of the study, which addresses the research question of whether SDT can predict social instability, is described in a brief paragraph. My suggestion is to extend the explanation of these results and go deeper into them. You could go further in the explanation of the magnitude of the parameters, test if the prediction would stand for a bigger time horizon, or identify which structural variable is more important to the prediction (which appears to be an important aspect in the Discussion section).

The last section of the results shows the interaction of two of the dimensions of SDT. This is coherent with the theory that stays that there are feedback loops between the variables. It is not clear why this was the only interaction tested. I suggest stating in the introduction a clear research question that is answered by this analysis, explaining in the results section why it is the only interaction addressed, or extending this section to include tests for other interactions.

As a final comment for this section, I would like to emphasize that these results discuss predictability but do not establish causality. I strongly recommend being cautious in making any claims that imply causation has been proven.

Discussion:

The discussion gives a rich explanation of the Chilean case and why it is in line with the results of the study. Although I think this is very valuable, it would be important to mention something about the policy implications of your results, taking into account that in the introduction you stated “Understanding the structural forces that underlie the dynamics of political instability in modern societies is essential to adopt measures that allow adapting social systems prior to the irruption of events” What can a policy maker learn from your study? I would also like to see some discussion about the implication of the results to SDT.

I find the mention of social distress in other countries highly relevant, considering that these countries likely exhibit significant variations in structural variables. It is of course beyond the scope of this study, but it would be interesting to see comparative studies of SDT.

Methods:

I cannot stress enough the recommendation of putting this section before results. Besides that, I suggest declaring more clearly that not only the model of SDT but also the measures are based on Turchin’s previous work. That would limit questions to the construction of structural variables and indexes.

This section should also explain the sources used for every measure and include more information that clarifies and justifies the chosen methods. Most of this is already written in supporting information, but it should be explained to some extent in the body of the paper.

Two last important points. The data provided do not meet PLOS politics. The data points used to create the provided aggregated measures, as well as the code used to process the information, should be included. Also, the financial disclosure link is broken.

Second evaluator

The paper presents a novel methodological and theoretical proposal for the analysis of socio-political dynamics in the Chilean context. The structural demographic theory is introduced and applied to approach the process of overproduction of the Chilean government elites and its relationship with the processes of mobilization and social conjuncture that the country has experienced. This aspect is in fact an element to be highlighted since it allows us to approach an understanding of the complex phenomena of social mobilizations and contributes to the development of future research in the región.

The following are a series of formal comments to be taken into consideration by the authors:

1) While it is true that at the introductory level the authors address the Structural Demographic Theory and the way it will be applied in the study, I suggest expanding a little more in detail on the scope of this theory to the study of social dynamics. Social demographic theory provides a conceptual framework for understanding patterns of population change at different stages of a country's socioeconomic development. The authors have supported with an exhaustive level of detail the methodological guidelines to account for the dynamics of change in the Chilean context with the variables for this purpose. However, the reader may have the feeling that the complex framework that Chile has experienced in this period (1938-2019) is reduced to a brief analysis of variables, omitting the complexity of the political, social, cultural, and historical reality of the country.

2) The phenomenon of social mobilizations is in essence a complex phenomenon and obeys the particularity of a specific context and time. Several elements have been mentioned that accompany the emergence of mobilization. While it is true that the authors mention in the introductory section of the manuscript, I quote: "Therefore, SDT does not seek to encompass all the complexity associated with the phenomenon of political conflict in social systems, nor does it ignore the importance of the agency of political actors. It only allows us to predict, through the interaction of structural variables, periods when the collective mood is more likely to trigger major scenarios of institutional instability" and in fact, the study does not seek to reduce the complexity of the social reality of Chile and the social mobilizations of October 18 to an analysis of variables, I suggest that the authors expand in more detail in the introductory section these elements of discussion.

3) The manuscript is structured from an introductory section followed by a middle section that introduces the reader to the findings of the study and then the reader will find a methodological section. I suggest that the methodological section comes first before the results. The manuscript is accompanied by supplementary material that the reader can consult to go into more detail on how the analysis proceeded. Nevertheless, the material contains important information that would be worth including in the methodological section of the article. To expand on the details of the procedure, the collection of the empirical corpus, the databases consulted, the previous works consulted. It would be more convenient for the reader to find this information in the methodological section and leave the more technical information guiding the methodological elaboration of the study in the supplementary file. Equations etc.

4) Finally, I suggest to the authors to expand the discussions of the study in terms of the scope of this research for the development of future studies in the region. How the use of Demographic Structural Theory can be a conceptual framework to address regional inequalities and disparities orchestrated by the elites. In terms of the challenges for the case of Chile to agitate planning processes and public policies for the future. By understanding the stages of transition that Chile has experienced in its history, it would be possible to infer changes in the population structure and think about the possibility of adapting policies in areas such as health, education, employment, social security, etc.

General considerations of the Academic Editor:

I suggest that the following recommendations of the evaluators be prioritized

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

b. Has the statistical analysis been performed appropriately and rigorously? NO

c. Have the authors made all data underlying the findings in their manuscript fully available? NO

d. Change the order of the sections of the article (method before results)

==============================

Please submit your revised manuscript by Aug 24 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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Academic Editor

PLOS ONE

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Additional Editor Comments:

First evaluator

This paper presents an interesting application of Structural Demographic Theory (SDT) to the case of Chile in the last century. It mostly draws on Goldstone and Turchin’s work, but it seems to go a bit further in terms of methodology by incorporating predictive analytics. The model used achieves to predict social unrest periods, leading the authors to argue that it shows the “underlying cause of Chilean political instability”. Although I think this is a very interesting piece of work, I believe it would benefit from some changes that I would suggest hereafter:

First, I will address some form issues.

I recommend modifying the title of the article to explicitly indicate that it is an application of SDT. That way it would be easier to identify the paper as a part of a broader literature, and would make it more accessible to a wider audience beyond those specifically interested in the Chilean case. Second, I suggest moving the materials and methods section before Results. Such order is common among PLOS articles and it would make a lot easier to understand the results section. Lastly, it appears that there are some issues with the equations when exporting from the text editor (see lines 73 and 348) and some equations seem to have errors (I’m guessing in eq 1 frequency and total occurrence are indexed in i).

Introduction:

This section seems very clear to me. It frames adequately SDT as an “interpretative framework” that “does not seek to encompass all the complexity” behind political instability but is sufficient to model (and predict) social unrest periods. In terms of the explanation of the Chilean case, it is weird that it goes into detail about social unrest during 2019, but does not address other important political instability events during the time window studied. It seems important to provide contextual information on political instability throughout the 20th century in Chile, as the study later treats at least two other events with the same level of importance as the "social outbreak" of 2019.

Results:

Once the goal of the study is introduced, the paper jumps to the results section with a visual inspection of four time series, one for each independent variable and one for an index that aggregates them with a multiplicative model. The visual inspection closes with a big conclusion: “it can be seen how the structural demographic theory predicts an increase in political tension in the Chilean social system prior to the outbreak of the main events of social instability of the last 80 years”. This is one of the main reasons why I recommend putting the methods section before. As I read this without knowing the methods that were going to be used to test predictability, it was easy to conclude the study was flawed. Visual inspection does not support predictability. I suggest either removing this initial part of the results or moderating the conclusion.

Then, the outcome of the model is presented. The authors introduce the Observed Political Instability Index (OPII) and while it can be inferred that this measure represents the dependent variable created by the authors, it would be a lot clearer if the methods section were before the results.

Finally, prediction models are presented: a non-linear regression proves that SDT can fit OPII, Arima model shows a temporal correlation between changes in observed and estimated outcomes, and forecasting provides evidence that SDT can predict the OPII using information from a year before. Unfortunately, this core aspect of the study, which addresses the research question of whether SDT can predict social instability, is described in a brief paragraph. My suggestion is to extend the explanation of these results and go deeper into them. You could go further in the explanation of the magnitude of the parameters, test if the prediction would stand for a bigger time horizon, or identify which structural variable is more important to the prediction (which appears to be an important aspect in the Discussion section).

The last section of the results shows the interaction of two of the dimensions of SDT. This is coherent with the theory that stays that there are feedback loops between the variables. It is not clear why this was the only interaction tested. I suggest stating in the introduction a clear research question that is answered by this analysis, explaining in the results section why it is the only interaction addressed, or extending this section to include tests for other interactions.

As a final comment for this section, I would like to emphasize that these results discuss predictability but do not establish causality. I strongly recommend being cautious in making any claims that imply causation has been proven.

Discussion:

The discussion gives a rich explanation of the Chilean case and why it is in line with the results of the study. Although I think this is very valuable, it would be important to mention something about the policy implications of your results, taking into account that in the introduction you stated “Understanding the structural forces that underlie the dynamics of political instability in modern societies is essential to adopt measures that allow adapting social systems prior to the irruption of events” What can a policy maker learn from your study? I would also like to see some discussion about the implication of the results to SDT.

I find the mention of social distress in other countries highly relevant, considering that these countries likely exhibit significant variations in structural variables. It is of course beyond the scope of this study, but it would be interesting to see comparative studies of SDT.

Methods:

I cannot stress enough the recommendation of putting this section before results. Besides that, I suggest declaring more clearly that not only the model of SDT but also the measures are based on Turchin’s previous work. That would limit questions to the construction of structural variables and indexes.

This section should also explain the sources used for every measure and include more information that clarifies and justifies the chosen methods. Most of this is already written in supporting information, but it should be explained to some extent in the body of the paper.

Two last important points. The data provided do not meet PLOS politics. The data points used to create the provided aggregated measures, as well as the code used to process the information, should be included. Also, the financial disclosure link is broken.

Second evaluator

The paper presents a novel methodological and theoretical proposal for the analysis of socio-political dynamics in the Chilean context. The structural demographic theory is introduced and applied to approach the process of overproduction of the Chilean government elites and its relationship with the processes of mobilization and social conjuncture that the country has experienced. This aspect is in fact an element to be highlighted since it allows us to approach an understanding of the complex phenomena of social mobilizations and contributes to the development of future research in the región.

The following are a series of formal comments to be taken into consideration by the authors:

1) While it is true that at the introductory level the authors address the Structural Demographic Theory and the way it will be applied in the study, I suggest expanding a little more in detail on the scope of this theory to the study of social dynamics. Social demographic theory provides a conceptual framework for understanding patterns of population change at different stages of a country's socioeconomic development. The authors have supported with an exhaustive level of detail the methodological guidelines to account for the dynamics of change in the Chilean context with the variables for this purpose. However, the reader may have the feeling that the complex framework that Chile has experienced in this period (1938-2019) is reduced to a brief analysis of variables, omitting the complexity of the political, social, cultural, and historical reality of the country.

2) The phenomenon of social mobilizations is in essence a complex phenomenon and obeys the particularity of a specific context and time. Several elements have been mentioned that accompany the emergence of mobilization. While it is true that the authors mention in the introductory section of the manuscript, I quote: "Therefore, SDT does not seek to encompass all the complexity associated with the phenomenon of political conflict in social systems, nor does it ignore the importance of the agency of political actors. It only allows us to predict, through the interaction of structural variables, periods when the collective mood is more likely to trigger major scenarios of institutional instability" and in fact, the study does not seek to reduce the complexity of the social reality of Chile and the social mobilizations of October 18 to an analysis of variables, I suggest that the authors expand in more detail in the introductory section these elements of discussion.

3) The manuscript is structured from an introductory section followed by a middle section that introduces the reader to the findings of the study and then the reader will find a methodological section. I suggest that the methodological section comes first before the results. The manuscript is accompanied by supplementary material that the reader can consult to go into more detail on how the analysis proceeded. Nevertheless, the material contains important information that would be worth including in the methodological section of the article. To expand on the details of the procedure, the collection of the empirical corpus, the databases consulted, the previous works consulted. It would be more convenient for the reader to find this information in the methodological section and leave the more technical information guiding the methodological elaboration of the study in the supplementary file. Equations etc.

4) Finally, I suggest to the authors to expand the discussions of the study in terms of the scope of this research for the development of future studies in the region. How the use of Demographic Structural Theory can be a conceptual framework to address regional inequalities and disparities orchestrated by the elites. In terms of the challenges for the case of Chile to agitate planning processes and public policies for the future. By understanding the stages of transition that Chile has experienced in its history, it would be possible to infer changes in the population structure and think about the possibility of adapting policies in areas such as health, education, employment, social security, etc.

General considerations of the Academic Editor:

I suggest that the following recommendations of the evaluators be prioritized

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

b. Has the statistical analysis been performed appropriately and rigorously? NO

c. Have the authors made all data underlying the findings in their manuscript fully available? NO

d. Change the order of the sections of the article (method before results)

[Note: HTML markup is below. Please do not edit.]

Reviewers' 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: Partly

**********

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

Reviewer #1: Yes

Reviewer #2: No

**********

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: Yes

Reviewer #2: No

**********

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

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

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 paper presents a novel methodological and theoretical proposal for the analysis of socio-political dynamics in the Chilean context. The structural demographic theory is introduced and applied to approach the process of overproduction of the Chilean government elites and its relationship with the processes of mobilization and social conjuncture that the country has experienced. This aspect is in fact an element to be highlighted since it allows us to approach an understanding of the complex phenomena of social mobilizations and contributes to the development of future research in the region, applied to other Latin American countries due to their proximity, to the extent that the so-called social outbreak of October 18, 2019 constituted an important precedent in the history of the country and the feeling of social struggle managed to energize and be reflected in contexts such as the Colombian one, which in the middle of the third peak of the pandemic, the country took to the streets in massive marches.

The following are a series of formal comments to be taken into consideration by the authors:

1) While it is true that at the introductory level the authors address the Structural Demographic Theory and the way it will be applied in the study, I suggest expanding a little more in detail on the scope of this theory to the study of social dynamics. Social demographic theory provides a conceptual framework for understanding patterns of population change at different stages of a country's socioeconomic development. The authors have supported with an exhaustive level of detail the methodological guidelines to account for the dynamics of change in the Chilean context with the variables for this purpose. However, the reader may have the feeling that the complex framework that Chile has experienced in this period (1938-2019) is reduced to a brief analysis of variables, omitting the complexity of the political, social, cultural, and historical reality of the country.

2) The use of the Demographic Structural Theory may be subject to criticism from approaches related to the theory of social mobilizations, in addition to the fact that the latter has been mostly used in the Latin American context, which have focused on human agency as a characteristic dimension of the subjects to make use of the environments and forge transformation processes. It is also necessary to highlight the place of social conflicts as an enabling dimension of the emergence of change, of the struggle against social injustices, inequality and in many cases oppression that are generated in certain classes, groups, and social movements. The political dimension is a relevant factor, insofar as the relationship between social movements and struggles develops in parallel with political processes, forging mechanisms that enable changes in the political structure. Similarly, the identity dimensions involved in social movements are fundamental factors, given that historically it has been known that a large part of social mobilizations emerge around the defense of identities such as race and ethnicity, and involve cultural and symbolic values in the processes of social struggle.

3) The phenomenon of social mobilizations is in essence a complex phenomenon and obeys the particularity of a specific context and time. Several elements have been mentioned that accompany the emergence of mobilization. While it is true that the authors mention in the introductory section of the manuscript, I quote: "Therefore, SDT does not seek to encompass all the complexity associated with the phenomenon of political conflict in social systems, nor does it ignore the importance of the agency of political actors. It only allows us to predict, through the interaction of structural variables, periods when the collective mood is more likely to trigger major scenarios of institutional instability" and in fact, the study does not seek to reduce the complexity of the social reality of Chile and the social mobilizations of October 18 to an analysis of variables, I suggest that the authors expand in more detail in the introductory section these elements of discussion.

4) The manuscript is structured from an introductory section followed by a middle section that introduces the reader to the findings of the study and then the reader will find a methodological section. I suggest that the methodological section comes first before the results. The manuscript is accompanied by supplementary material that the reader can consult to go into more detail on how the analysis proceeded. Nevertheless, the material contains important information that would be worth including in the methodological section of the article. To expand on the details of the procedure, the collection of the empirical corpus, the databases consulted, the previous works consulted. It would be more convenient for the reader to find this information in the methodological section and leave the more technical information guiding the methodological elaboration of the study in the supplementary file. Equations etc.

5) Finally, I suggest to the authors to expand the discussions of the study in terms of the scope of this research for the development of future studies in the region. How the use of Demographic Structural Theory can be a conceptual framework to address regional inequalities and disparities orchestrated by the elites. In terms of the challenges for the case of Chile to agitate planning processes and public policies for the future. By understanding the stages of transition that Chile has experienced in its history, it would be possible to infer changes in the population structure and think about the possibility of adapting policies in areas such as health, education, employment, social security, etc.

Reviewer #2: This paper presents an interesting application of Structural Demographic Theory (SDT) to the case of Chile in the last century. It mostly draws on Goldstone and Turchin’s work, but it seems to go a bit further in terms of methodology by incorporating predictive analytics. The model used achieves to predict social unrest periods, leading the authors to argue that it shows the “underlying cause of Chilean political instability”. Although I think this is a very interesting piece of work, I believe it would benefit from some changes that I would suggest hereafter:

First, I will address some form issues. I recommend modifying the title of the article to explicitly indicate that it is an application of SDT. That way it would be easier to identify the paper as a part of a broader literature, and would make it more accessible to a wider audience beyond those specifically interested in the Chilean case. Second, I suggest moving the materials and methods section before Results. Such order is common among PLOS articles and it would make a lot easier to understand the results section. Lastly, it appears that there are some issues with the equations when exporting from the text editor (see lines 73 and 348) and some equations seem to have errors (I’m guessing in eq 1 frequency and total occurrence are indexed in i).

Now I will address the contents of the paper going section by section.

Introduction:

This section seems very clear to me. It frames adequately SDT as an “interpretative framework” that “does not seek to encompass all the complexity” behind political instability but is sufficient to model (and predict) social unrest periods. In terms of the explanation of the Chilean case, it is weird that it goes into detail about social unrest during 2019, but does not address other important political instability events during the time window studied. It seems important to provide contextual information on political instability throughout the 20th century in Chile, as the study later treats at least two other events with the same level of importance as the "social outbreak" of 2019.

Results:

Once the goal of the study is introduced, the paper jumps to the results section with a visual inspection of four time series, one for each independent variable and one for an index that aggregates them with a multiplicative model. The visual inspection closes with a big conclusion: “it can be seen how the structural demographic theory predicts an increase in political tension in the Chilean social system prior to the outbreak of the main events of social instability of the last 80 years”. This is one of the main reasons why I recommend putting the methods section before. As I read this without knowing the methods that were going to be used to test predictability, it was easy to conclude the study was flawed. Visual inspection does not support predictability. I suggest either removing this initial part of the results or moderating the conclusion.

Then, the outcome of the model is presented. The authors introduce the Observed Political Instability Index (OPII) and while it can be inferred that this measure represents the dependent variable created by the authors, it would be a lot clearer if the methods section were before the results.

Finally, prediction models are presented: a non-linear regression proves that SDT can fit OPII, Arima model shows a temporal correlation between changes in observed and estimated outcomes, and forecasting provides evidence that SDT can predict the OPII using information from a year before. Unfortunately, this core aspect of the study, which addresses the research question of whether SDT can predict social instability, is described in a brief paragraph. My suggestion is to extend the explanation of these results and go deeper into them. You could go further in the explanation of the magnitude of the parameters, test if the prediction would stand for a bigger time horizon, or identify which structural variable is more important to the prediction (which appears to be an important aspect in the Discussion section)

The last section of the results shows the interaction of two of the dimensions of SDT. This is coherent with the theory that stays that there are feedback loops between the variables. It is not clear why this was the only interaction tested. I suggest stating in the introduction a clear research question that is answered by this analysis, explaining in the results section why it is the only interaction addressed, or extending this section to include tests for other interactions.

As a final comment for this section, I would like to emphasize that these results discuss predictability but do not establish causality. I strongly recommend being cautious in making any claims that imply causation has been proven.

Discussion:

The discussion gives a rich explanation of the Chilean case and why it is in line with the results of the study. Although I think this is very valuable, it would be important to mention something about the policy implications of your results, taking into account that in the introduction you stated “Understanding the structural forces that underlie the dynamics of political instability in modern societies is essential to adopt measures that allow adapting social systems prior to the irruption of events” What can a policy maker learn from your study? I would also like to see some discussion about the implication of the results to SDT.

I find the mention of social distress in other countries highly relevant, considering that these countries likely exhibit significant variations in structural variables. It is of course beyond the scope of this study, but it would be interesting to see comparative studies of SDT.

Methods:

I cannot stress enough the recommendation of putting this section before results. Besides that, I suggest declaring more clearly that not only the model of SDT but also the measures are based on Turchin’s previous work. That would limit questions to the construction of structural variables and indexes.

This section should also explain the sources used for every measure and include more information that clarifies and justifies the chosen methods. Most of this is already written in supporting information, but it should be explained to some extent in the body of the paper.

Two last important points. The data provided do not meet PLOS politics. The data points used to create the provided aggregated measures, as well as the code used to process the information, should be included. Also, the financial disclosure link is broken.

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Reviewer #1: No

Reviewer #2: No

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Squeezed from the top: “Social Outburst” (2019) and elite overproduction. A study of the dynamics of Chilean political instability from the approach of Structural Demographic Theory.

PONE-D-23-15713R1

Dear Dr. Muñoz-Rodríguez,

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