Transport Accessibility of Warsaw: A Case Study

Round 1

Reviewer 1 Report

First of all, I want to thank for the opportunity to revise this interesting manuscript.

The study mainly aims at determining which means of transportation is time-wise beneficial in which parts of Warsaw. 

I have found the manuscript well organized, and clearly written. Overall, the study design is appropriated, and the results presented by the Authors are interesting. Thus, I think that the study could be of interest to the readers, but in my opinion, some major revisions are required before its publishing.

In particular:

1) Introduction section. This section is too long. I suggest to shorten it by shifting the study area description (starting from line 108) into a devoted Methods paragraph. Furthermore, the final sentence (lines 142-146) better fits in the conclusion section, as it is an Authors' consideration.

2) Results section. Table no. 2 reports the same analysis performed using both Pearson and Spearman correlation coefficients. Why do the Authors choose to use both the coefficient for the same variables? Did the Authors perform a parametric test?

3) Discussion section. In my opinion, this section is interesting, but it lacks one important observation, which can strengthen the study findings. In facts, there is no reference to an important issue, related to the active transportation propensity: the traffic accidents particularly referred to the more sensitive users (pedestrians - children and elderly - and cyclist). I suggest the Authors discuss how the choice in using a different way of transportation (instead of the car-using), can reflect in a reduction of traffic accidents, mostly in the parts of the city where there is a concentration of activities and interests, which are largely recognized as walkable and liveable areas. 

I suggest to consider the following articles, which may be useful:

Congiu, T. et al. Built Environment Features and Pedestrian Accidents: An Italian Retrospective Study. Sustainability 2019, 11, 1064. Stoker, P. et al. Pedestrian Safety and the Built Environment: A Review of the Risk Factors. J. Plan. Lit. 2015, 30, 377–392. NACTO. NACTO Urban Street Design Guide; National Association of City Transportation Officials: New York, NY, USA, 2012.

4) Conclusion section. Please delete lines 445-446.

I hope the authors will consider the suggestion, as I believe that the study will be well received by readers.

Author Response

We would like to thank anonymous reviewers for their valuable comments. They provided useful suggestions to clarify the research questions, results and their signification. The paper, revised on the basis of your recommendations, includes a number of changes, which we consider very positive. We appreciate all your insightful comments which will be also very useful in our future research work also.

Detailed responses to the comments: please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

This case study examines transport accessibility of Warsaw using spatial analysis. Study is interesting and I do not have any major concern. Some questions and minor concerns are:

Introduction section is quite large. It would be better to have a subsection of Study Area (starting from Line 108). Perhaps, it could be added into Methods. Big data was mentioned on line 144 without giving any particular context or way how to join current analysis/data with big data to explore/answer accessibility problems in Warsaw. Please provide details or remove “big data”. There is no need to mention “Source: own work” on figures and tables. Line 179-180: I am not sure who the centroids of the grid cells were compatible with the measurement points used for travel time calculations. What is the rational of using weights of BDOT features? How authors come up with weight of 20 for Stations and terminals, 0.1 for play and sports grounds etc.? It would be helpful to include transit lines and railway on a figure. Figure 4: I think labels of b & c are switched. Left figure should be 4b) public transport and right should be 4c) bicycle. Figure 4: Why car driving time has continuous color scheme and others don’t? How data (travel time, weighted normal, potential accessibility) were categories/grouped? Line 380-381: I don’t think it is contrary or surprising to common perception that a car is faster mean of travel then other means.

Conclusion should provide summary of the study and final thoughts. In its current form, mostly it provides limitation of the study and should be included in Discussion section (perhaps as last paragraph or subsection) and conclusion should be rewritten.

Author Response

We would like to thank anonymous reviewers for their valuable comments. They provided useful suggestions to clarify the research questions, results and their signification. The paper, revised on the basis of your recommendations, includes a number of changes, which we consider very positive. We appreciate all your insightful comments which will be also very useful in our future research work also.

Detailed responses to the comments: please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

Topic of the paper is interesting and important. The paper is useful. Described methodology may be used for other cities.

In my opinion literature review is at good level.

Line 171: Authors should explain, why they chose 2 a.m., 8 a.m., 12 p.m., 5 p.m., and 9 p.m., as hour to make research. Especially 2 a.m. hour should be explained. Why they did not select for example 6 or 7 a.m. and 2 p.m. or 4 p.m.?

Line 230: "for each cell for public transportation and car travel, we gathered 3000 measurements." However - line 168: "On the basis of Google Maps, for each measurement point, the travel time to the other 600 points was calculated along with the distance and speed."? 600 x 600 = 360,000 and for 5 different time points means 1,800,000 and even only for car and public transport means 3,600,000 values. By 600 cells equal 6000 per cell.

Authors should more explain how many routes by time and distance were found in Google Maps and what kind of measurements were mentioned in line 230.

Authors should also explain why they used Google Maps in the research, why they think results from Google Maps are enough for that kind of research. How about road congestion accuracy? I do not question the validity of such data, but the explanation should be found in the paper.

Equation (5) and lines 274,275. There is no tii or tij in the equation. Authors should correct it.

Author Response

We would like to thank anonymous reviewers for their valuable comments. They provided useful suggestions to clarify the research questions, results and their signification. The paper, revised on the basis of your recommendations, includes a number of changes, which we consider very positive. We appreciate all your insightful comments which will be also very useful in our future research work also.

Detailed responses to the comments: please see the attachment.

Author Response File: Author Response.docx

Reviewer 4 Report

This is an interesting article on an important topic. I enjoyed reading the work. There are some minor comments that I would like to point out which I believe would enhance the article, especially with respect to the hot topic of employing open data for smart and efficient transportation.

In introduction, line 28, you correctly point out that solutions are based on data analysis. Afterwards you discuss data selection importance and methods, but forget to point our the new trend in using Open data platforms for solving daily life problems including transportation. For instance, OpenStreetMap is a porject that provide open geospatial data for routing and navigation and there are several studies about OSM for transportation including:

- Efficient planning of urban public transportation networks. In 

International Conference on Ubiquitous Computing and Ambient Intelligence

 (pp. 439-448). Springer, Cham. - Assessing the completeness of bicycle trails and designated lane features in OpenStreetMap for the United States and Europe. In 

Transportation Research Board Annual Meeting

- A mixed reality interface for real time tracked public transportation. In 

Proceedings of the 10th ITS European Congress

 (Vol. 9, pp. 1-6). Furthermore, there are several studies using OSM data for accessible urban transportation which is also an important issue raised in your article. Please see for instance:

- Are crowdsourced datasets suitable for specialized routing services? Case study of OpenStreetMap for routing of people with limited mobility. 

Sustainability, 9(6), 997. - Wheelmap: the wheelchair accessibility crowdsourcing platform. 

Open Geospatial Data, Software and Standards, 2(1), 27. Please note that although open data initiatives in Poland might not be strong but regardless of that OSM is a worldwide project and the data of OSM should be quite good esp. in capital of Poland. Even if not, there are studies about this to introduce methods for improvement of the quality of data in OSM, for example see this study which is the outcome of a European Union study on transportation: - OpenStreetMap data quality enrichment through awareness raising and collective action tools—experiences from a European project. 

Geo-spatial Information Science, 21(3), 234-246. I do understand that the main focus of this paper is not on open data, but I find it important for readers to also be aware of this hot topic, and it is also good for you to express the fact that you are aware of this trend. I suggest that you include this studies in introduction and well as ideas for future work. 

Author Response

We would like to thank anonymous reviewers for their valuable comments. They provided useful suggestions to clarify the research questions, results and their signification. The paper, revised on the basis of your recommendations, includes a number of changes, which we consider very positive. We appreciate all your insightful comments which will be also very useful in our future research work also.

Detailed responses to the comments: please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I believe that the quality of the manuscript has improved, and the article can be accepted in the present form.