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  • 1.
    Ait Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Eliasson, Jonas
    Linköpings universitet.
    Warg, Jennifer
    KTH.
    Are commuter train timetables consistent with passengers’ valuations of waiting times and in-vehicle crowding?2020Report (Other academic)
    Abstract [en]

    Many models have been developed and used to analyse the costs and benefits of transport investments. Similar tools can also be used for transport operation planning and capacity allocation. An example of such use is the assessment of commuter train operations and service frequency. In this study, we analyse the societally optimal frequency for commuter train services. The aim is to reveal the implicit valuation (by the public transport agency) of the waiting time and the in-vehicle crowding in the commuting system. We use an analytic CBA model to formulate the societal costs of a certain service frequency and analyse the societally optimal frequencies during peak and off-peak hours. Comparing the optimal and the actual frequencies allows to reveal the implicit valuations of waiting time and crowding. Using relevant data from the commuter train services in Stockholm on a typical working day in September 2015 (e.g., OD matrix, cost parameters), we perform a numerical analysis on certain lines and directions. We find the societally optimal frequency and the implicit valuation of waiting time and crowding. The results suggest that the public transport agency in Stockholm (i.e., SL) adopted service frequencies that are generally slightly higher than societally optimum which can be explained by a higher implicit valuation of waiting time and crowding. We also find that the optimal frequencies are more sensitive to the waiting time valuation rather than that of crowding.

  • 2.
    Ait Ali, Abderrahman
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Eliasson, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Measuring the Socio-economic Benefits of Train Timetables: Application to Commuter Train Services in Stockholm2017In: 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary, Elsevier, 2017, Vol. 27, p. 849-856Conference paper (Refereed)
    Abstract [en]

    On highly used railway lines with heterogeneous traffic, timetabling is challenging. In particular, the limited existing capacity means that to guarantee an acceptable level of quality, the infrastructure manager must cancel some train services on the expense of others. In this article, we study the conflict between commercial long-distance trains and subsidized commuter trains with a socio-economic perspective (i.e. travelers and train operators). The study attempts to answer the following question: What is the socio-economic effect of modifying the timetable of a commuter service?The case study treats the commuter train services in Stockholm. Trip data was collected from the local commuter train operator. An entropy maximization-based model was implemented to estimate the dynamic network Origin-Destination (OD) matrix. This dynamic matrix, of one full working day, was then used to estimate the number of travelers per train, and further converted for use in the microscopic simulation tool RailSys. Travel and waiting time are estimated for each OD pair and with that the generalized costs for the travelers and operators. The effect of crowding in the trains is included in the estimation. The article can be considered as an initiation to a novel method to calculate effects of changes in commuter train timetables. This novel approach enables to price commercial train slots in the capacity allocation process such as in an auction. It provides a new way to estimate the local train operator´s valuation of the different parameters (i.e. waiting, travel time and interchanges). Using RailSys for the estimation of times makes it possible to include capacity aspects that normally are difficult to reveal.

  • 3.
    Ait Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Warg, Jennifer
    KTH.
    Eliasson, Jonas
    Linköpings universitet.
    Pricing commercial train path requests based on societal costs2019Report (Other academic)
    Abstract [en]

    On deregulated railway markets, efficient capacity allocation is important. We study the case where commercial trains and publicly controlled traffic (“commuter trains”) use the same railway infrastructure and hence compete for capacity. We develop a method that can be used by an infrastructure manager trying to allocate capacity in a socially efficient way. The method calculates the loss of social benefits incurred by changing the commuter train timetable to accommodate a commercial train path request and based on this calculates a reservation price for the train path request. If the commercial operator’s willingness-to-pay for the train path exceeds the loss of social benefits, its request is approved. The calculation of social benefits takes into account changes in commuter train passengers’ travel times, waiting times, transfers and crowding, and changes in operating costs for the commuter train operator(s). The method is implemented in a microscopic simulation program, which makes it possible to test the robustness and feasibility of timetable alternatives. We show that the method is possible to apply in practice by demonstrating it in a case study from Stockholm, illustrating the magnitudes of the resulting commercial train path prices. We conclude that marginal societal costs of railway capacity in Stockholm are considerably higher than the current track access charges.

  • 4.
    Fröidh, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Sipilä, Hans
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Capacity for express trains on mixed traffic lines2014In: International Journal of Rail Transportation, ISSN 2324-8386, Vol. 2, no 1, p. 17-27Article in journal (Refereed)
    Abstract [en]

    Mixed traffic with large speed differences between fast and slower trains consumesmore capacity and makes the system sensitive to disruptions. This article focuses onadequate train configuration for increasing the top speed for express trains like theGreen Train and how that affects capacity on lines with heterogeneous traffic.Microscopic simulation of a future timetable selected by criteria revealed by analyticaltimetable analysis for a chosen structure of services combines the advantages of twomethods and makes it possible to reveal relevant characteristics for different alternatives.Punctual short stops through better train layout and skip-stop operation forregional trains are a few of the measures that are shown to have compensating effectsfor the increase in capacity utilisation and can reduce disruptions. Although it ispossible to reduce the perturbations by means of different measures, the basic problemwith mixing fast and slower trains on the same line still remains.

  • 5.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Economic evaluation of timetable strategies with simulation2013Conference paper (Refereed)
    Abstract [en]

    Capacity shortfalls on railway lines often lead to disturbances in operation and limited possibilities for traffic increase. Static and dynamic characteristics describing the capacity are an important input for cost-benefit analysis. However, they are rarely used in economics. At the same time, economic parameters are hardly ever included in capacity studies.

    This paper focuses on measurements of dynamic timetable and capacity characteristics. The purpose is to identify the determining variables that influence capacity and by the railway users. Is simulation a useful method to reveal the decisive parameters? A structure for economic evaluation of the identified characteristics is to be developed.

    Using mixed methods data analysis, relevant capacity characteristics are retrieved and relationships between these, static criteria and socio-economic impacts identified. The study is mainly based on passenger rail traffic between Stockholm and Gothenburg in Sweden and the focus is on long-distance passenger traffic. Simulation is shown to be advantageous as future scenarios can be evaluated concerning operational parameters – which according to the results of this paper are important to travelers. A structure for a future model where timetable analysis and microscopic simulation are used to reveal relevant capacity characteristics based on the findings is presented.

  • 6.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Effects of increased traffic volume and speed heterogeneity on the capacity of a railway with dense mixed traffic2012In: Computers in Railways XIII: Computer System Design and Operation in the Railway and Other Transit Systems, WIT Press, 2012, p. 485-497Conference paper (Refereed)
    Abstract [en]

    Increasing demand for train travel implies a need for improved traffic. More frequent departures and new regional stops have to be coordinated with the desire to shorten travel times for passengers and on the same line be mixed with freight operations. This paper analyses how increased traffic predicted for 2020 affects the capacity of a 400-km section of the Southern Main Line in Sweden, a highly-utilised double-track line with heterogeneous and dense traffic with low punctuality, particularly as regards high-speed trains. In a second step, the consequences of raising the maximum speed for high-speed trains from 200 to 250 km/h are analysed. The purpose of the paper is to show the effects of these measures and discuss strategies for improving punctuality and increasing timetable flexibility based on the revealed weaknesses of the system by combining timetable analysis and simulation. The evaluation shows that an increase in traffic volume and speed differences leads to a decrease in the flexibility and reliability of the timetable. The punctuality of the high-speed trains becomes unacceptably low. The tested approaches to normalise the effects of increased traffic and speed on flexibility and punctuality are shown to be insufficient. Capacity utilisation on the line is so high that recovery is not possible.

  • 7.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. Järnvägsgruppen.
    Timetable evaluation with focus on quality for travellers2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Punctuality and reliability are important for travellers. Railway lines with heterogeneous and dense traffic have proved to be prone to generate delays. Faster services and increased traffic have to be counterbalanced with measures for increased reliability. Efficient timetable planning can improve the use of such lines. Usually, that aim is treated from either a capacity or a socio-economic point of view. Because both are important, this thesis aims to combine the fields. A new method to evaluate timetable alternatives is developed. Commonly used methods are combined in a novel way to reveal values for different variables as input for evaluation of alternatives. That enables the comparison of timetable strategies using relevant input data. The idea is to estimate the benefits of a timetable for a traveller by expressing them as a timetable performance index (TTPI). For this purpose, quality indicators and methods to reveal them are identified. In the next step, traditional valuations for relationships between the indicators are used to test different model configurations for evaluation of alternatives, for example alternative departures on the same line or different timetables. 

    To treat this multidisciplinary task, several case studies were performed on the Swedish Southern and Western Main lines. As part of a study focussing on methods to measure and evaluate capacity based on travellers’ valuations, the importance of delays was analysed in a questionnaire study and relationships between several variables describing the timetable were found. The other case studies aimed to identify relevant variables and use them to evaluate alternatives. Static and dynamic variables are distinguished. The static ones describe the timetable before operation, the dynamic ones the result of operation or estimated outcome revealed by means of, for example, simulation. Empirical delay data is used in one study, simulation with the microscopic tool RailSys in the others. In one of the studies, analysis is combined with the macroscopic timetabling tool TVEM (Lindfeldt, 2010). The case studies showed the characteristics of the analysed lines described by the chosen variables and which methods and variables are relevant to use for a comparison of timetable slots or evaluation of effects of changes in the timetable. An evaluation method was developed where simulation and timetable analysis reveal the variables. The idea is to construct an analytical function using traditional weights for relationships between the variables to convert the values of the variables into a performance index (PI). Based on a PI for each train slot (TSPI), the TTPI for the whole timetable is estimated. It describes the quality of a timetable in terms of timetable time, i.e. the resulting value is a time that is comparable to the scheduled travel time of one train departure, but includes additional information. With this method, complex timetables can be evaluated regarding their robustness to perturbations, which is valuable for socio-economic analysis of effects of measures applied on the railway system.

    As shown in a one of the case studies, quality in terms of punctuality and reliability is important for travellers, at the same time as the design of the timetable has significant impact on these aspects. Timetable analysis and simulation are relevant methods to reveal variables that describe these characteristics and evaluation with the presented method is recommended. The configuration of the TTPI is essential for the outcome whereas it is important to choose variables and parameters adequately. If this is taken into account, the approach can be an efficient way to adjust timetables and choose the best alternative, for instance if a train path or timetable change is to be chosen among several.

  • 8.
    Warg, Jennifer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Utvärdering av tidtabellsalternativ med hjälp av simulering2015In: Transportforum, Linköping, 2015, 2015Conference paper (Other (popular science, discussion, etc.))
  • 9.
    Warg, Jennifer
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport Planning, Economics and Engineering.
    Ait-Ali, Abderrahman
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport Planning, Economics and Engineering.
    Eliasson, Jonas
    Assessment of Commuter Train Timetables Including Transfers2019In: 21st EURO Working Group on Transportation Meeting, EWGT 2018, 17th – 19th September 2018, Braunschweig, Germany, 2019, Vol. 37, p. 11-18Conference paper (Refereed)
    Abstract [en]

    Many railway networks suffer from high capacity utilisation. For scheduling all services, adjustments to the desired slots are often needed. Such adjustments might lead to longer travel times, crowded trains, longer waiting times for boarding and for transfers. All of this has an important socio-economic impact on both travellers and train operators. This raises the question of the socio-economic assessment of changes in commuter train timetables including transfers. Thus, the aim of this study is to evaluate the effects of adjustments of commuter train timetables on the traveller (i.e. consumer costs) and the train operator (i.e. producer costs). These costs are estimated based on all train trips and operations in the network. In a case study, the effect of changes in departure times (resulting in non-regular interval timetables) is analysed. Further, the price of cancelling a two-way service during different times of the day is compared. The results show that changing departure times can both decrease and increase the total costs, and that regularity for parallel services might not be as important as expected if it is kept for each separate service. For the second study, waiting times for transfers were indicated to have a (too) large impact which can lead to misleading results and might be adjusted in future work. The model is adequate for such kind of questions but needs some more adjustments. For railway networks with dense and heterogeneous traffic (as is the case in Sweden), the contributions of this model are useful for making the challenging timetabling process easier and commuter train services less costly.

  • 10.
    Warg, Jennifer
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Bohlin, Markus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering. Mälardalens Högskola.
    The Use of Railway Simulation as an Input to Economic Assessment2015Conference paper (Refereed)
    Abstract [en]

    Capacity is an important factor for assessing a railway. Capacity limitations restrict the possibilities to adjust the service supply to the market demand and can lead to disturban­ces that affect the travellers negatively. For this reason, it is important that the available capacity and the effects of using it are estimated and assessed when benefits are analysed. However, estimations often focus on either socio-economic or capacity aspects only.

    In this paper, a method for evaluating timetable alternatives using time equivalents by combining economic assessment and capacity analysis is developed. Parameters describing each alternative´s characteristics and their effect are stepwise added to an existing model. Both real and simulated delay statistics for express trains on a double-track line with dense, mixed traffic are used to first determine relevant input parameters and calibrate the model, and later compare different alternatives. The results show that the choice of input parameters for the delays and the way how to include them in the model affected the result to a large extent. That highlights the importance of making adequate classifications of data and choosing the right parameters. Simulation is suitable for estimating the effect of changes on reliability which is an important input in an estimation model combining capacity and socio-economic aspects.

  • 11.
    Warg, Jennifer
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Bohlin, Markus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    The use of railway simulation as an input to economic assessment of timetables2016In: Journal of Rail Transport Planning & Management, ISSN 2210-9706, E-ISSN 2210-9714Article in journal (Refereed)
    Abstract [en]

    Assessment of capacity for highly-used railways is an important and challenging task. This paper describes a method for evaluation of timetables based on capacity and economic assessment. Common methods from both fields are combined. For developing and analysing purposes, the model is first tested with historical delay data for express trains on a double-track line with dense, mixed traffic in Sweden. An assessment aiming to compare the departures is made by combining common weights for different variables. Differences in the results based on the model structure are discussed. In the second step, microscopic simulation is used to reveal delay characteristics of timetable alternatives that are then compared and discussed in a similar way to step 1.

    The presented method using simulation makes it possible to reveal and evaluate characteristics that are important for both timetable planning and economic analysis, for example evaluation of strategies. Timetable and delay times are important input variables that affect the travellers' choice. Using simulation and other methods from capacity planning gives the opportunity to find characteristics for analysing alternatives and improve economic evaluation, at the same time as the use of economic parameters provides more possibilities to make a relevant capacity analysis.

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