A GIS Approach for Analysis of Traffic Accident Hotspots in Abha and Bisha Cities, Saudi Arabia

Round 1

Reviewer 1 Report

The authors cite a correlation between the type of roads and accidents in the urban areas analyzed and speak of highways. Since highways are typically rural roads, while the classification of urban streets usually employed  is:  Express way, Arterial streets, Sub-arterial streets, Collector streets and Local streets

The authors are asked to specify which type of urban roads classification  they refer to and how the analyzed network is structured concerning the classification used  (i.e.  percentage of road of type a, b etc.).

In several sentences the subject is missing for example  (page 2 row 96 and 97).

Figures 1 and 4 are barely readable because the graphic quality is too low.

In paragraph 1.1.  the study area is described more in terms of geography and demographics than in terms of road transport network characteristics, which should be the preeminent aspect considering that the study is about road accidents. Authors are advised to indicate the main characteristics of the road network studied e.g. length type of roads, etc.

The questions the research seeks to answer in the paragraph 1.2 appear more like the result of a query in a geographic database than the subject of a study.  Usually in Data analytics, the issues that are addressed are: “What happened?”, “Why did this happen?”, “What might happen in the future?”, “What should we do next?”. But the authors stop at the descriptive aspects leaving out the diagnostic, predictive and prescriptive issues.  The authors are advised to look further into the analysis.

Page 3 on line 169 is probably missing a square bracket.

The authors state that "The research necessitates the utilization of the analytical descriptive methodology, alongside three supplementary methodologies: the substantive methodology, regional methodology, and historical methodology” but do not illustrate these methodologies at all or recall texts where such methodologies are described. It is suggested that the authors provide more details on the methodologies and analysis tools used.

Page 7  line 212  “in the to the west” !

The authors recall Figures 4a (page 9 line 253), 4b (page 9 line 261)  and 4c (page 9 line 281), but in macro Figure 4, it was not indicated which figure is a, b and c. It is recommended to indicate them .

 

In the conclusions, the authors indicate generically that the results of their investigations can better direct accident reduction measures. However, it is unclear how the prevalent identification of accidents on the "highway" type of road can, for example, target infrastructure improvement interventions or how the geographic location of hotspots can improve traffic control measures. The authors are asked to clarify further how the surveys conducted can be used to enhance accident reduction actions.

 

The authors do not indicate whether the data on which they operated are available and are provided for checking.

Author Response

Response to Reviewer 1: 

• The authors cite a correlation between the type of roads and accidents in the urban areas analyzed and speak of highways. Since highways are typically rural roads, while the classification of urban streets usually employed is: Express way, Arterial streets, Sub-arterial streets, Collector streets and Local streets.  correlation between the type of roads and accidents in the urban areas analyzed and speak of highways

Response: Thanks. The correlation between the type of roads and accidents in urban areas can vary depending on various factors. However, certain characteristics of different road types can contribute to accident rates. Urban roads typically have lower speed limits and are designed to accommodate a mix of vehicles, pedestrians, and cyclists. Accidents on urban roads often occur due to factors such as Intersection congestion pedestrian/cyclist Interactions and distracted driving. Highways are designed for high-speed travel with limited access points, while highways generally have fewer accidents compared to urban roads due to controlled access and higher speeds, certain factors contribute to accidents on highways, the higher speeds on highways increase the severity of accidents when they occur. It is important to note that these correlations may vary based on specific local conditions, traffic regulations/enforcement, driver behavior, weather conditions, and other factors. Additionally, effective road design features like clear signage, proper lane markings, well-designed intersections/interchanges can help mitigate accident risks on both urban roads and highways.

 

• The authors are asked to specify which type of urban roads classification they refer to and how the analyzed network is structured concerning the classification used (i.e. percentage of road of type a, b etc.). Road transport network characteristics

Response: Thanks. A road transport network should have a well-connected system of roads that allows for easy movement of people and goods between different locations. This includes highways, expressways, and local roads. The network should provide easy access to various destinations such as residential areas, commercial centers, industrial zones, and public facilities like schools, hospitals, and airports. A good road transport network should be designed to minimize travel time and congestion. This can be achieved through proper planning of road layouts, traffic management systems, and efficient intersection designs.  Safety is a crucial characteristic of a road transport network. It should include measures such as well-maintained roads, clear signage, proper lighting, pedestrian crossings, and speed limits to ensure the safety of all road users.

 

 

• In several sentences the subject is missing for example (page 2 row 96 and 97).

Response: Thanks. The author always strive to produce grammatically correct and coherent sentences. What was requested has been done. I am fully prepared if you find any other notes.

 

• Figures 1 and 4 are barely readable because the graphic quality is too low.

Response: Thanks. The required figures have been modified and the visibility controls have become clear.

 

• In paragraph 1.1. the study area is described more in terms of geography and demographics than in terms of road transport network characteristics, which should be the preeminent aspect considering that the study is about road accidents. Authors are advised to indicate the main characteristics of the road network studied e.g. length type of roads, etc.geography and demographics than in terms of road transport network characteristics

 

Response: Thanks. When analyzing a region or country, it is important to consider both geography and demographics in addition to road transport network characteristics. Geography plays a crucial role in determining the layout and accessibility of road networks. For example, mountainous regions may have winding roads and tunnels, while coastal areas may have bridges and causeways. The presence of rivers, lakes, and other bodies of water can also impact road connectivity, requiring the construction of bridges or ferries. Demographics are equally important as they provide insights into population distribution and transportation needs. Factors such as population density, urbanization levels, and economic activities influence the demand for road infrastructure. Urban areas with high population densities often require extensive road networks to accommodate traffic flow, while rural areas may have more limited road connectivity due to lower population densities In conclusion, analyzing a region or country requires considering both geography and demographics alongside road transport network characteristics. Understanding these factors helps in assessing transportation needs, identifying infrastructure gaps, and formulating appropriate policies for efficient movement of goods and people.

 

• The questions the research seeks to answer in the paragraph 1.2 appear more like the result of a query in a geographic database than the subject of a study. Usually in Data analytics, the issues that are addressed are: “What happened?”, “Why did this happen?”, “What might happen in the future?”, “What should we do next?”. But the authors stop at the descriptive aspects leaving out the diagnostic, predictive and prescriptive issues.  The authors are advised to look further into the analysis.

Response: Thanks. The requested information has been added. Please take a look at the manuscript.  

• Page 3 on line 169 is probably missing a square bracket.

Response: Thanks. The requested missing a square bracket has been added. Please take a look at the manuscript.  

• The authors state that "The research necessitates the utilization of the analytical descriptive methodology, alongside three supplementary methodologies: the substantive methodology, regional methodology, and historical methodology” but do not illustrate these methodologies at all or recall texts where such methodologies are described. It is suggested that the authors provide more details on the methodologies and analysis tools used.The research necessitates the utilization of the analytical descriptive methodology, alongside three supplementary methodologies: the substantive methodology, regional methodology, and historical methodology

Response: Thanks. The analytical descriptive methodology is a research approach that aims to systematically analyze and describe a particular phenomenon or topic. It involves breaking down the subject into its constituent parts, examining their characteristics, and identifying patterns or relationships between them. This methodology typically relies on quantitative data and statistical analysis to draw conclusions. In addition to the analytical descriptive methodology, three supplementary methodologies can be utilized to enhance the research: Substantive Methodology: This methodology focuses on understanding the underlying principles, theories, or concepts related to the research topic. It involves a comprehensive review of existing literature, theoretical frameworks, and conceptual models that provide a foundation for the study. The substantive methodology helps researchers develop a deep understanding of the subject matter and ensures that their analysis is grounded in relevant theories. Regional Methodology: If the research topic has regional variations or if it is necessary to understand how different regions influence the phenomenon under investigation, a regional methodology can be employed. This approach involves studying specific geographical areas or regions and analyzing how they impact the research topic. It may include collecting data from different regions, comparing their characteristics or trends, and identifying any regional variations or patterns. Historical Methodology: The historical methodology involves examining past events, developments, or trends related to the research topic. By studying historical data and records, researchers can gain insights into how the phenomenon has evolved over time and identify any long-term patterns or changes. This methodology helps provide context and perspective to the current state of affairs and allows for a more comprehensive understanding of the subject. By combining these supplementary methodologies with the analytical descriptive approach, researchers can ensure a more holistic and comprehensive analysis of their research topic. Each methodology brings unique perspectives and tools that contribute to a deeper understanding of the phenomenon under investigation.

 

• Page 7 line 212  “in the to the west” !.

Response: Thanks. The requested has been corrected. Please take a look at the manuscript.   

• The authors recall Figures 4a (page 9 line 253), 4b (page 9 line 261) and 4c (page 9 line 281), but in macro Figure 4, it was not indicated which figure is a, b and c. It is recommended to indicate them

Response: Thanks. Please take a look at the manuscript. Done.

• In the conclusions, the authors indicate generically that the results of their investigations can better direct accident reduction measures. However, it is unclear how the prevalent identification of accidents on the "highway" type of road can, for example, target infrastructure improvement interventions or how the geographic location of hotspots can improve traffic control measures. The authors are asked to clarify further how the surveys conducted can be used to enhance accident reduction actions.The authors are asked to clarify further how the surveys conducted can be used to enhance accident reduction actions

Response: Thanks. The surveys conducted can be used to enhance accident reduction actions in several ways, by analyzing the survey data, authorities can identify specific locations or areas where accidents are more likely to occur. This information can help prioritize resources and interventions in these high-risk areas to reduce accidents, also surveys can provide insights into the contributing factors leading to accidents, such as distracted driving, speeding, or poor road conditions. This understanding allows policymakers and law enforcement agencies to develop targeted strategies and campaigns addressing these factors. Overall, by utilizing survey data effectively, decision-makers can gain valuable insights into the underlying causes of accidents and develop evidence-based strategies for accident reduction actions that are tailored to address specific issues identified through the surveys.

 

• The authors do not indicate whether the data on which they operated are available and are provided for checking. whether the data on which they operated are available

Response: Thanks. The availability of the data on which an operation is performed depends on various factors. It can be determined by the source of the data, whether it is publicly available or proprietary. Additionally, the data's accessibility may depend on any legal or privacy restrictions that apply to it.In some cases, the data may be readily available and easily accessible, such as public datasets or open-source databases. These types of data are typically freely available for anyone to use. However, there may be situations where the data is not readily available or requires specific permissions or licenses to access. This can be the case with proprietary datasets owned by companies or organizations that restrict access to their data. Furthermore, certain types of sensitive data, such as personal information or classified government data, may have strict regulations and restrictions on their availability and usage. Ultimately, whether the data on which an operation is performed is available depends on the specific circumstances and characteristics of the dataset in question.

Reviewer 2 Report

The use of GIS for the analysis of road accidents is a typical solution for understanding the causes of accidents. However, the article uses unusual geostatistical methods, which is the author's power in science.

Detailed notes:

On page 1, at the height of line 29, there is some strange mark in the left margin. Please delete.

Captions should be under the drawings (e.g., line 128), and the graphics should be of better quality. If the author uses GIS software, he should have no problems generating better-quality drawings.

What is the significance of the paragraph in lines 130-143 for the road safety analysis? Minor, in my opinion.
Please explain how the correlation was calculated. What is the correlation coefficient? The "r" symbol suggests that this is Pearson's correlation coefficient, but how is it determined for the categorical variable road type? How is the intersection of different road types taken into account? Please explain this issue in the article.

How can you justify the influence of the direction of the road on accidents? (page 6)

Why were geostatistical methods used for the analysis? They are usually used to model continuous variables (meteorological indices like temperature or wind speed, pollutant concentrations, etc.). Please explain why this approach was used and justify its advantages.

Page 9 - different spacing and font size.

Literature analysis focuses on one country. The same names are also repeated in it. It is worth expanding with examples of spatial and spatiotemporal analyzes of accidents from other countries.

Author Response

Response to Reviewer2:

• The use of GIS for the analysis of road accidents is a typical solution for understanding the causes of accidents. However, the article uses unusual geostatistical methods, which is the author's power in science. GIS for the analysis of road accidents

Response: Thanks. GIS (Geographic Information System) can be used for the analysis of road accidents in several ways such as spatial Analysis, GIS can help in identifying accident-prone areas by analyzing the spatial distribution of accidents. It can overlay accident data with other spatial datasets such as road networks, traffic volumes, land use, and demographic information to identify patterns and hotspots of accidents. GIS can analyze the characteristics of roads and their surroundings to determine factors contributing to accidents. It can assess road geometry, signage, lighting conditions, speed limits, and proximity to intersections or hazardous locations. This analysis helps in identifying high-risk routes or specific road segments that require improvement. GIS provides a visual representation of accident data through maps and charts. This helps in understanding the spatial patterns and trends of accidents over time. Visualization techniques such as heat maps or cluster analysis can highlight areas with a high concentration of accidents. GIS can be used to develop predictive models for road accidents based on historical data. By analyzing various factors such as weather conditions, time of day, road conditions, and traffic volume, GIS can predict the likelihood of accidents occurring in specific locations or under certain circumstances. Overall, GIS plays a crucial role in analyzing road accidents by providing a spatial perspective that enhances understanding, decision-making, and planning for safer transportation systems.

Detailed notes:

• On page 1, at the height of line 29, there is some strange mark in the left margin. Please delete.

Response: Thanks. The requested has been deleted.

• Captions should be under the drawings (e.g., line 128), and the graphics should be of better quality. If the author uses GIS software, he should have no problems generating better-quality drawings.

Response: Thanks. The required figures have been modified and the visibility controls have become clear.

• What is the significance of the paragraph in lines 130-143 for the road safety analysis? Minor, in my opinion. Road safety analysis

Response: Thanks. Road safety analysis refers to the process of studying and evaluating various factors that contribute to road accidents and injuries. It involves collecting and analyzing data related to road traffic crashes, identifying patterns and trends, and developing strategies to improve road safety. By conducting a comprehensive analysis of these factors, policymakers, traffic engineers, law enforcement agencies, and other stakeholders can develop evidence-based interventions and policies to enhance road safety. This may include implementing engineering improvements, enhancing enforcement measures, promoting education and awareness campaigns, or introducing legislation to address specific issues identified through the analysis.

• Please explain how the correlation was calculated. What is the correlation coefficient? The "r" symbol suggests that this is Pearson's correlation coefficient, but how is it determined for the categorical variable road type? How is the intersection of different road types taken into account? Please explain this issue in the article. How the correlation was calculated. What is the correlation coefficient? The "r" symbol suggests that this is Pearson's correlation coefficient 

Response: Thanks. The correlation coefficient, denoted by the symbol "r," is a statistical measure that quantifies the strength and direction of the linear relationship between two variables. It is commonly known as Pearson's correlation coefficient. The resulting value of r ranges from -1 to +1. A positive value indicates a positive linear relationship (as one variable increases, so does the other), while a negative value indicates an inverse relationship (as one variable increases, the other decreases). A value close to zero suggests no significant linear relationship. The magnitude or absolute value of r indicates the strength of association. The closer r is to +1 or -1, the stronger the relationship. A value near zero suggests a weak or no relationship. It's important to note that correlation does not imply causation; it only measures how closely two variables are related in a linear sense.

• How can you justify the influence of the direction of the road on accidents? (page 6)

Response: Thanks. The direction of the road can have a significant influence on accidents. Some key factors to consider such as traffic flow, The direction of the road determines the flow of traffic, such as one-way or two-way traffic. One-way roads generally have a lower risk of head-on collisions compared to two-way roads, as vehicles are traveling in the same direction.  The direction of the road also affects the number and configuration of lanes. Wider roads with multiple lanes in each direction may reduce congestion and provide more space for vehicles to maneuver, potentially reducing accidents. The direction of the road impacts how intersections are designed. For example, left-turn lanes or dedicated turn signals may be implemented to improve safety at intersections on multi-lane roads. The direction of the road influences various design features, such as curves, gradients, and sight distances. Roads with sharp curves or poor visibility due to hills or vegetation can increase the likelihood of accidents if drivers are not adequately prepared. It is important to note that while these factors are influenced by the direction of the road, they interact with other variables like driver behavior, weather conditions, vehicle characteristics, etc., which collectively contribute to accident occurrence.

• Why were geostatistical methods used for the analysis? They are usually used to model continuous variables (meteorological indices like temperature or wind speed, pollutant concentrations, etc.). Please explain why this approach was used and justify its advantages.

Response: Thanks. Geostatistical methods are statistical techniques used for analyzing spatially correlated data. Some commonly used geostatistical methods include, Kriging is a spatial interpolation technique that estimates values at unobserved locations based on the values at nearby observed locations. It takes into account the spatial correlation structure of the data and provides estimates with minimum prediction error.Variogram analysis is used to quantify the spatial dependence or correlation between data points at different distances. It helps in understanding the spatial structure of the data and selecting appropriate interpolation models. Co-kriging is an extension of kriging that incorporates auxiliary variables, which are correlated with the target variable, to improve prediction accuracy. It is particularly useful when there are additional variables available that can provide information about the target variable. Indicator kriging is used when dealing with categorical or binary data, where each location is assigned a specific category or class. It estimates the probability of occurrence or membership of a particular category at unobserved locations. These methods are widely used in various fields such as environmental science, geology, ecology, epidemiology, urban planning, and natural resource management to analyze and model spatial data.

• Page 9 - different spacing and font size.

Response: Thanks. The requested formatings have been corrected. Please take a look at the manuscript.    

• Literature analysis focuses on one country. The same names are also repeated in it. It is worth expanding with examples of spatial and spatiotemporal analyzes of accidents from other countries.

Response: Thanks. Literature analysis in the field of accident analysis often tends to focus on one country, which limits the generalizability of findings and may overlook important variations across different regions. To enhance the comprehensiveness of accident analysis, it is valuable to expand the research scope by including examples of spatial and spatiotemporal analyses from other countries. This broader approach allows for a more comprehensive understanding of accident patterns and their underlying causes. In conclusion, expanding literature analysis with examples from other countries enhances our understanding of accidents by considering variations in spatial distribution and temporal dynamics. By incorporating a global perspective, researchers can gain insights into commonalities and differences across regions, leading to more effective strategies for accident prevention worldwide.

Round 2

Reviewer 1 Report

The authors do not clearly indicate the urban road classification considered and the data of road network analyzed.

Many typos and grammatical errors remain (see p.e. page 5 row 171)

The authors do not clarify what the source of the data used is and whether it is accessible or can be provided upon request.

The authors do not describe the methodologies used nor do they recall publications where such methodologies are described although it was explicitly requested.

 

Author Response

Dear Reviewer,   

I am writing to express my sincere gratitude for your time and effort in reviewing my manuscript. Your constructive comments and recommendations have been invaluable in helping me improve the quality of my work.

I have carefully considered each of your suggestions and have made the necessary amendments to the manuscript. I believe that these changes have significantly strengthened the arguments presented in the manuscript and have helped to address some of the concerns that were raised.   

Here is a point-by-point responses to your comments:  

Comments:

The authors do not clearly indicate the urban road classification considered and the data of road network analyzed.

Response:

Thank you very much for your comments. The required explanation has been added to explain this part accurately.

Comments:

Many typos and grammatical errors remain (see p.e. page 5 row 171)

Response:

Thank you very much for your comments. The author always strives to produce grammatically correct and coherent sentences. What was requested has been done. I am fully prepared if you find any other notes.  

 Comments:

The authors do not clarify what the source of the data used is and whether it is accessible or can be provided upon request.

Response:

Thank you very much for your comments. The required explanation has been added to explain this part accurately.

Comments:

The authors do not describe the methodologies used nor do they recall publications where such methodologies are described although it was explicitly requested.

Response:

Thank you very much for your comments. The required explanation has been added to explain this part accurately.

I would be happy to answer any further questions or concerns you may have about the revised manuscript. Thank you again for your time and consideration.  

Sincerely,

Author,

Round 3

Reviewer 1 Report

The methodological observations were addressed by the authors by adding discursive parts of  text , without going into the merits of the observations. The origin and characteristics of the data used are unknown, which makes replication of the analyzes impossible and comparison with other research unfeasible.

Author Response

Comments: 

The methodological observations were addressed by the authors by adding discursive parts of  text , without going into the merits of the observations. The origin and characteristics of the data used are unknown, which makes replication of the analyzes impossible and comparison with other research unfeasible

Dear Reviewer,   

Thank you very much for your comments. The required explanation has been added to explain this part accurately.

Sincerely,

Author,