The Pedestrian Level of Service in Metro Stations: A Pilot Study Based on Passenger Detection Techniques

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript develops an observational approach to detect passengers and further estimate the service level in metro stations based on platform train interface. Five dimensions are considered including passenger behavior, train design, passengers characteristics, train operation, and platform

built environment. Overall, the paper is well written and its logic is clear to me. The reviewer has only a few questions or concerns:

 

Currently, there is a significant amount of research on the behavior of subway passengers at subway stations, which can be divided into macro and micro perspectives. Macro-level studies examine the travel behavior characteristics of passengers due to subway crowding, while micro-level studies focus on the detailed behavior of passengers on platforms or within train cars. It is recommended that the authors expand the current literature review to include more relevant studies, thereby better positioning and highlighting the contributions of this research within the existing body of work.

 

It is recommended that the authors provide a clearer introduction to the variables across the five dimensions and include more detailed description of their connection to the level of service.

 

Some important relevant references are missing, for example:

Li, Z., Lo, S. M., Ma, J., & Luo, X. W. (2020). A study on passengers’ alighting and boarding process at metro platform by computer simulation.

Fu, L., Chen, Q., Shi, Q., Chen, Y., & Shi, Y. (2023). Characteristics of pedestrians’ alighting and boarding process in metro stations.

 

It is suggested to list the limitations of this study in the conclusions (e.g., data accuracy limitation of different dimensions) to better understand the applicability of the research.

Comments on the Quality of English Language

Minor revision of English Language

Author Response

Dear Reviewer,

Thank you very much for reviewing the paper. We tried to address all of the comments as best as possible.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The idea behind the research is very sound and needed from a practical point of view. However, since this is a presentation of a procedure for estimating LOS, I am missing a better explanation of the concept, a longer observational period to test it in multiple LOS scenarios, and also a discussion where the authors would better point out the potential for use in other similar situations. My detailed comments are below.

The title should specify that this is pedestrian/passenger LOS.

How were the input parameters for the LOS determined? Based on what sources?

Why is the focus on overground metro stations? Are there significant differences between underground/under ground? Or "regular" train stations?

Some language issues, e.g. lines 58 to 64 use "it is expected.." which is not gramatically sound.

Line 61: does height mean the physical height of the passengers? Why does it matter?

Line 137: you mention that seat layout affects LOS which in turn affects capacity, but is this not the other way around? 

The literature review focuses on LOS, mostly for pedestrians, but the portion of LOS of train/metro stations is lacking. Since this is what you ultimately want to measure, I would expect a stronger focus on the overall LOS from the passenger viewpoint from multiple aspects. If I input ("train station" OR "metro station") AND "level of service" into a scientific database, I get a lot of papers which are very relevant for you and should be used as input into your criteria selection and engine.

Line 156 - finish the sentence

Why was this station chosen?

The observations were only done in peak hour, which I think is a major limitation. Please comment on this - why only one hour and why this hour?

Line 171: having a backpack does not define students. I'm a professor and I use a backpack.

Were the cameras set up for this purpose or are they stationary security cameras? How did you have access? What types of streams? Continuous or time lapse?

The calibration points - how were they chosen? What happens when a passenger moves around?

Figure 5: what do the lines represent?

You only measures the amount of people in one carriage, on six seats and one hall plus corridor? That is consequently a really small sample.

What parametres were defined for the LOS?

If I understand correctly, you measured the amount of people on the whole line (s from Puerto Station to Chorrillos Station (and viceversa))? Then why did you talk about a specific station?

Explain Figure 11 - what does moment of time mean?

The height cut off is most certainly set too low - 1.2 metres, according to WHO's charts, is the average height of 7 year olds: https://www.who.int/tools/growth-reference-data-for-5to19-years/indicators/height-for-age

Why does height matter?

The development of the model needs to be explained.

A discussion segment is missing - what do the results mean, how do they compare with previous LOS concepts for train and metro stations, what are the potential applications, limitations...

 

 

 

Comments on the Quality of English Language

Some minor improvements need to be made.

Author Response

Dear Reviewer,

Thank you very much for reviewing the paper. We tried to address all of the comments as best as possible.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The article I was asked to review concerns the qualification of the level of service (LOS) on the basis of videos of platforms and train interiors in a Valparaiso metro station in Chile. This qualification concerns 5 variables (passenger behaviour, train design, passenger characteristics, train operation, platform design). The results show that passenger speed is linked in particular to passenger density. 

On the whole, this article is clear and precise. However, there are a few points that could be improved:

There is a problem in defining the level of service. The term is frequently used to describe many different things related to the traveller experience. What I understand is that in your case, you are interested exclusively in the passenger flow level of service, which is never clearly expressed or supported by existing definitions.

Another problem linked to the previous one is that you never justify the choice of dimensions included in your model. Why these variables?

The way you describe the gaps in the literature (at the end of part 2) is a little superficial. You should clearly specify in detail what has been done and what has not been done in relation to what you are proposing.

There is an overlap between your height and type variables in the regression model analysis. They are one and the same, since height is used to determine whether adults or children are involved.

On other points of detail, an overall re-reading would be necessary to correct certain errors:
- page 3, "the problem with LOS is that is based".
- on page 4, the end of a paragraph is missing: "The area of the train floor".
- page 5, the observed stations (when you're only talking about one station)
- page 14, "adult passengers have a lower speed" when it seems to me that the opposite is true. - on page 5, I don't understand why you're talking about students here when they're not one of the variables being studied
- figure 3 is referenced instead of figure 4 at the beginning of page 5
- the way the graphs are presented on pages 8 and 9 does not allow for comparison

Author Response

Dear Reviewer,

Thank you very much for reviewing the paper. We tried to address all of the comments as best as possible.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I'm satisfied with the revisions. No further comments.