Isolating the Role of the Transport System in Individual Accessibility Differences: A Space-Time Transport Performance Measure

Round 1

Reviewer 1 Report

Paper is extremely well written, very clear and pedagogic piece of work.

 

L47 what is meant exactly by « discretionary activities » as opposed to « fixed activities » ; please explain otherwise the reasoning is not fluid to follow for a reader not familiar with accessibility literature

 

l53 « and transport policies cannot prevent it eliminate distance »

 

l183 how does this approach evaluates the fast transport systems, eg motorways, railways, that generates much more detour than slower ones eg classical road, bike. This phenomenon is refered to as « spatial inversion » in literature (Bunge 1962)

 

l189 does it integrate a value of time based on income?

 

L193 IDTC is presented in the diagram as based on a generalized cost while this idea is not expressed in the three principles in the text before; this used of generalized cost should be stated and justified beforehand

 

l193 the discretionary part of accessibility seems to be just removed in A-STA; nevertheless in the very idea of accessibility there is a matter of choice, of measuring “possible” activities, not actual activities performed; the proposed indicator will express nothing about what is possible just outside the fixed activities; giving zero values to the surrounding urban amenities; this is really a functionalist approach and not crediting the liveliness, vibrancy of urban space; this choice should be emphasized

 

l232 ASTA will in the end end-up as a measurement in euros per km, if we consider this is cost divided by straight line km; but this is not the effort of daily travel, rather the pure performance of transport system and stems from the individual perspective to focus on transport performance

 

table 3: it is not clear why many time eg for B identical activities “home-stay” are following up with seemingly missing sequences : what B does between 15:00 and 17:30? this information cannot be derived from the table; something is missing; and this is also the case for individual C, D and E; the move with no purpose indicated and then come back home

 

l322 revenue could have been derived from localized revenue data sources; some areas average revenue can be generally obtained since they do not entail the possibility to identifying individuals. Also alternative proxy for revenue is age or profession; indeed individual E is presented as student, then her/his revenue is necessary lower than the other individuals, and this should exert strong impacts on the measurement of A-STA

 

L361 the km considered in the value AKC are they euclidean or along the network, travelled; this is of importance for the analysis and should be precised

 

L362 typo “expressed ad the ration between” should be “expressed as the ratio between”

 

l375 I suggest “to the Euclidean (and not traveled actual) distance among fixed activities. Accordingly, the individuals experiencing”

 

l376 this would help to follow the argument “the lowest A-STA (D and B) are contrasted between those that register the highest average kilometric cost and detour effect”

 

table 5 would be nice to complete with the preferred mode of transport of each individual; this factor would help a lot to understand the cases, and is used in the commentaries

 

l408 typo “which fees ca????? 78% less than the standard subscription for adults”

 

l473 what is CV here?

 

I consider the so-called T-STA and A-STA measurement are way too different from each other to be compared; they measure completely different realities. Their designation implies a proximity that simply does not exist; simply stated the very unit of each measurement, abstract unit for T-STA but akin to a number of opportunities accessible, and €/km for A-STA that refer to a performance of a unit of movement – the km – indicates how different the measurement are; in consequence the rhetoric of the article, the idea of introducing an alternative measurement of accessibility, is undermined; the very input of the paper is on the side of a complimentary measurement to classical accessibility measurement, as is indeed expressed in the section titles “caveats” which are not really caveats but rather the discussion of what this measurement can bring in complement to the classical accessibility measurement. The proposed measurement should be called completely differently to not imply a false, rhetoric proximity with the measurement of accessibility.

 

 

Author Response

Please see the attachment.

There you find a general response to the editors and reviewers, as well as a point-by-point response to each comment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Good paper. Comments:

A. L299: 5km/h also for individual D?

B. L417: free time would be important on PT.

C. Authors state they focus on methodology, not on statistical analysis. Therefore there is no need for referring to improvements from statistical analysis (L437, L479), which is evident.

Typos etc:

1. L128: "results are"
2. L189: "non-monetary cost"
3. L201: "an"=?
4. Table 2: "fixty"=?
5. L223: "weighed"
6. L259: "most significant extension"=?
7. L267: "once defined the study area"=?
8. Table 3, bottom: "activity"
9. Table 4, bottom: "vales"=?
10. L362: "ad the ration"=?
11. L391, 419, 451, 462: "on the one side/on the other side" should be changed to "on the one hand/on the other hand" 
12. L408: "which fees"=?

Author Response

Please see the attachment.

There you find a general response to the editors and reviewers, as well as a point-by-point response to each comment.

Author Response File: Author Response.pdf

Reviewer 3 Report

The article makes a positive impression, has a complete look. In the introduction, the authors fully outlined the relevance of the study, highlighting 2 reasons for the failure of existing indicators of individual accessibility: the inevitability of individual differences in accessibility that the transport system cannot correct, and the uncertainty of the activities types of individuals. The article is well structured, the goal is highlighted.

The literature review highlights the advantages and disadvantages of two groups of transport accessibility indicators based on place and person.  In the next section, the authors describe their alternative space-time accessibility measure and compare its calculation process with the traditional space-time accessibility measure. Further, on a specific example, the features of the calculation and comparison of the results of assessing transport accessibility by traditional and alternative measures are given. In the conclusions, the authors, highlighting the limitations of the proposed method, objectively outlined the prospects for its application in the existing methodological system.

While a clear and consistent style of presentation should be noted, it remains unclear why the 60% and 45% shares respectively for drivers and passengers when calculating a single travel time cost were chosen. It would also be useful in conclusion to indicate more clearly for solving which practical problems in the development of the city transport system as a whole the proposed method can be useful.

I would like to suggest to the authors in further studies:

1. in view of the development of ideas about the transport sustainability, add a comparison of the transport accessibility for people using means of individual mobility (scooters, bicycles, etc.).
2. to measure how transport accessibility will change when walking sections are replaced by the use of means of individual mobility?
3. to distinguish between the cost of an hour for different people, using average earnings values ​​typical for groups of the same employment.

Thank you for the opportunity to read the articles and good luck in your further research.

Author Response

Please see the attachment.

There you find a general response to the editors and reviewers, as well as a point-by-point response to each comment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

I appreciate the significant efforts conducted by the authors to address my remarks, including the most profound, and I consider the new paper suitable for publication.