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  • 1.
    Ahmad Termida, Nursitihazlin
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Understanding Individuals' Learning and Decision Processes in a Changing Environment by Using Panel Data2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    When a new transport service is introduced, people have to learn and familiarize themselves with the new service before they decide to adopt it. These processes are developed over time, thus produce dynamics in individuals’ behavioural responses towards the service. This affects the demand of the new service, thus affect revenues. Available studies have examined the factors influencing these responses from microeconomic perspectives. The influence of the theory-based subjective factors has not been examined empirically. Understanding these would assist transport and urban planners to design a better marketing strategy to increase the market share of the new service. A change in seasons affect individuals’ activity-travel decisions, thus produce dynamics in activitytravel patterns in different seasons. Individuals’ constraints, in a form of mandatory activities (working/studying), are influencing individuals’ decisions to participate in day-to-day nonmandatory activities (leisure and routine activities). The interdependency between travel demand, time allocation and mode choice that considers interactions between mandatory and non-mandatory activities, in different seasons is less explored. Understanding these would assist transport planners and operators to manage travel demand strategies across different seasons of the year and provide better transportation systems for all individuals. This thesis includes five papers. Paper I explores individuals’ characteristics of the quick-response and the adopters of the new public transport (PT) service and examines the temporal effects. Paper II investigates the subjective factors influencing a quick-response to the new PT service by proposing a modified attitude-behaviour framework. Paper III and IV analyse the effects of seasonal variations and individuals’ constraints on their day-to-day activity-travel decisions and patterns. Paper V analyses the attrition and fatigue in the two-week travel diary panel survey instrument.

  • 2.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Franklin, Joel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Attrition and Fatigue in a Four Waves of Two-Week Travel Diary: A Case Study in Stockholm, SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    This paper describes a four-wave panel survey design and implementation collected on individual level, consisting of three survey’s instrument namely, self-reported two-week travel diary, on-line psychological questionnaire, and self-reported mental map-related questions. The panel survey is built with the aim to examine individuals’ behavioural changes when a new tram extension line in western sub-urban areas of Stockholm, Sweden, was introduced in October 2013. The survey duration took approximately seven months’ period and the data collected covers all four different seasons of the year, which make it wealth of information. The analysis of attrition and fatigue was done on the two-week travel diary survey instrument only. It is found that the overall attrition rate is 34.3% of the total participants (102 individuals) in the Wave 1 survey, which is considered large. The attrition rate between consecutive waves, however, is considered low which is within the range of 7% to 10%. Based on the binary logit models, there are no systematic tendencies of the dropouts’ characteristics from wave to wave to be found, indicating attrition is purely random. There is no correlation between immobile days and missing trips per day are to be found between-waves. The results of the binary logit model on missing trip show that personal attributes, temporal factors (e.g. weekdays and waves) and travel characteristics (e.g. home-based trip, trip purpose, travel distance and number of inter-modal transfers) significantly affect the missing trip but no indication of fatigue appears.

  • 3.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Franklin, Joel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Subjective Factors Influencing Individual's Response to a New Public Transport ServiceManuscript (preprint) (Other academic)
    Abstract [en]

    The timing and nature of people’s responses can be expected to vary when a new element enter their environment. For example, when an individual is provided with a new or modified transport service. This time-scale of behavioural responses will affect the patronage of, and short- and long-term demands on the new service over time. Understanding the underlying factors that influence an individual’s response over time to a new or modified transport service would enable us to identify trigger factors that make the new service attractive from an individual’s point of view. Chatterjee (2001) and Douglas (2003) argued that motives other than instrumental factors related to public transport use, such as attitudes, awareness, travel habits and learning processes, can influence individual responses over time to changes in the travel environment. Unfortunately, despite their importance, there have been few studies that examined this argument empirically. To address this research gap, this paper aims to investigate the influences of subjective factors on individuals’ responses to the introduction of a modified public transport (PT) service over time by proposing and testing an alternative model that modifies the theory of planned behaviour (TPB) model framework. This paper also aims to investigate the behavioural change in terms of attitudes and perceptions on individuals’ resources and constraints in using a modified PT service over time after its introduction. The case study involves the new extension of a tram line connecting the suburbs of Alvik and Solna Centrum in Stockholm, Sweden. Four waves of a panel survey were conducted with 96 individuals who lived along the new service, from just before the new service was introduced and until seven months after its introduction. A structural equation modelling technique was used to estimate the relationships between behavioural constructs and panel data, then incorporate them into a discrete choice model. The results show that intention influences individual’s quick-response choice. The panel analysis shows that past behaviour in using the new service influenced current behaviour, and that perceived walking distance in using the service consistently influenced the frequency of using the new service over time.

  • 4.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Franklin, Joel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Liu, Chengxi
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. VTI.
    Understanding Seasonal Variation in Individual's Activity Participation and Trip Generation by Using Four Consecutive Two-Week Travel DiaryManuscript (preprint) (Other academic)
    Abstract [en]

    This paper explores the interactions between travel demand, time allocation and mode choice in different seasons by jointly modeling the work and/or study, routine and leisure activity-travel engagements of 67 individuals in Stockholm, Sweden. A longitudinal panel two-week travel diary data collected in four consecutive waves over a span of seven months period that covers all four different seasons; autumn, winter, spring and summer, were analysed by using simultaneous Tobit models. The model was applied to explore the interactions among each activity-travel indicator, and individuals’ unique characteristics and endogeneity in activity-travel engagements between different seasons were also considered in the model system. The results of models reveal clear trade-offs between mandatory activities (work and/or study) and non-mandatory activities (routine and leisure), regardless of any seasons, although the magnitudes vary between seasons. There is also a positive mutual endogeneity relationship between number of trips and activity duration within the same activity type. The trade-offs between work and/or study trips towards routine and leisure trips are larger in winter and spring respectively, than in other seasons. It is also found that mode effects on travel time for conducting mandatory activity are much larger in spring than in other seasons. However, the effects of public transport and slow modes on travel time for leisure activities are much larger in summer than in other seasons.

  • 5. Allström, A.
    et al.
    Kristoffersson, Ida
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. cVTI Swedish National Road and Transport Research Institute, Sweden.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Smartphone based travel diary collection: Experiences from a field trial in Stockholm2017In: Emerging technologies and models for transport and mobility 44th European Transport Conference Selected Proceedings, Casa Convalescència, Barcelona, Spain, 5-7 October 2016, Elsevier, 2017, Vol. 26, p. 32-38Conference paper (Refereed)
    Abstract [en]

    Currently, there is a great need for new methods to collect travel data. Traditional methods have considerable drawbacks and, at the same time, the models used to analyse the transport system require more and more detailed and high-quality data. An alternative method that stands out as very promising is to capture raw data from devices that can use any positioning technology (e.g., GPS, WiFi positioning, GSM, etc.), followed by transforming the raw data into meaningful travel data. Since most smartphones are equipped with various sensors that can be used to determine the location of the smartphone, and since smartphones are integrated in the daily life of most people, they provide an unprecedented opportunity for large-scale travel data collection. This method has a great potential to solve the problems related to the estimation of distance/travel time, geographic coding of departure/destination locations and forgotten trips and it will also provide a more detailed and extensive data set. In a recently completed research project the feasibility of replacing or complementing the traditional travel diary, with a suite of tools that make use of smartphone collected travel data has been evaluated. The advantages and disadvantages of the traditional method and the proposed method were studied. For a fair comparison, both methods have been tested in the same city, at the same time, and with the same respondents. To achieve the objectives of the project, MEILI, a system that consists of a smartphone application for capturing the movement of users and a web application for allowing the users to annotate their movement, has been deployed. The recruitment of respondents is a critical phase for traditional travel diaries and, as expected, this was the case also for the smartphone based method. A lesson learnt was that it is important to simplify the registration process as much as possible. In total 2142 trips were collected and annotated by 171 users. 51 of the users annotated trips covering more than a week. The experiences from the field trial shows that a smartphone based travel diary collection is a very useful complement to traditional travel diary collection methods since it appeals to a different age group and collects more detailed travel data for a longer period. The main findings of the paper are that smartphone based data collection is feasible, that the algorithms to save battery work well and that trips of the same respondent vary considerably depending on day of the week.

  • 6.
    Almström, Peter
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System analysis and economics. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Three essays on transport CBA uncertainty2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cost Benefit Analysis (CBA) has for a long time been used in transport planning, but it is often questioned. One main argument against CBA is that the results depend largely on assumptions regarding one or a few input factors, as for example the future fuel price or valuation of CO2 emissions.

    The three papers included in this thesis investigate some aspects of uncertainty in transport CBA calculations. The two first papers explore how changes in input data assumptions affect the CBA ranking of six rail and road investments in Stockholm. The first paper deals with the effect of different land-use assumptions while the second deals with the influence of economic growth, driving cost and public transport fare. The third paper investigates how alternative formulations of the public transport mode choice and route choice affect travel flows, ticket revenues and consumer surplus. These are important factors previously known to affect CBA results.

    The findings of the first two papers suggest that CBA results are robust concerning different land-use scenarios and single input factors. No change in rank between a road and a rail object is observed in the performed model calculations, and only one change between two road objects. The fact that CBA results seem robust regarding input assumptions supports the use CBA as a tool for selecting transport investments. The results in the third paper indicate that if there is detailed interest in, for example, number of boardings and ticket income from a certain transit line, or the total benefit of a price change, a more detailed formulation of the public transport mode choice and route choice will provide more reliable results. On the other hand, this formulation requires substantially more data on the transit line and price structure than the conventional formulation used in Swedish transport planning, especially in areas with many different pricing systems.

  • 7.
    Almström, Peter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Berglund, Svante
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Jonsson, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    The impact of travel costs and economic growth on cost-benefit analysis rankings2012Manuscript (preprint) (Other academic)
    Abstract [en]

    The use of Cost-benefit analysis (CBA) as a tool for selecting transport investments is often questioned. It is not unusual that politicians or others in the public debate argue that the outcome of a CBA completely rely on assumptions concerning a particular input factor, such as valuation of CO2 emissions or future fuel price. This paper explores whether the relative ranking of CBA outcomes are robust with respect to some key inputs in transport demand analysis driving cost, public transport fare and economic growth. We study six different infrastructure objects (three road and three rail objects) and four alternative assumptions on input factors compared to a reference scenario.

    The findings suggest that single input factors in a CBA, individually have a small impact on the ranking of the studied investments. In our model calculations we observe no change in rank between a road and a rail object.

  • 8.
    Almström, Peter
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Engelson, Leonid
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Modelling the effect of transit supply and price structure on mode choice and route choice2011Conference paper (Refereed)
    Abstract [en]

    This paper develops a new mode choice and transit route choice model for work trips by either car or transit. In contrast to the conventional regional traffic models used for transportation planning in Sweden, the model accounts for the fact that the value of time varies within a population of travellers making a trip with the same purpose and the fact that the price can differ between different transit lines (bus, regional trains, etc.). A mixed binomial logit (MXL) model with a lognormally distributed cost parameter has been estimated for the mode choice. The MXL specification makes it possible to capture some of the variation in the value of time. The transit route choice model rests on the assumption that transit commuters purchase travel passes that are valid for a certain time period, e.g. a month. The travel pass then allows the traveller to use a certain set of transit lines, while others are not available. For the mode choice, the traveller compares travel cost and time with the chosen pass with the travel cost and time by car. The results from performed analyses indicate that if the interest is in overall mode share and overall travel flows, the conventional method in Swedish transport modelling will suffice. However, if the interest is more detailed, for example concerning boardings and ticket income from a certain transit line, or the total benefit of a price change, the model developed in this paper will give more reliable results.

  • 9.
    Andersson, Matts
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science. WSP Analysis & Strategy Sweden.
    Berglund, Moa
    Floden, Jonas
    Persson, Christer
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Waidringer, Jonas
    A method for measuring and valuing transport time variability in logistics and cost benefit analysis2017In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 66, p. 59-69Article in journal (Refereed)
    Abstract [en]

    The freight transport system is subject to delays and disturbances, which influence investment and planning decisions made by governments and infrastructure authorities. Traditionally relying on Cost Benefit Analysis (CBA) they are dependent on correct and up-to-date input data. So far, little success has been reached in estimating the effects of disturbances for freight. This paper aims to contribute to the understanding of disturbances in freight transport by reviewing and classifying the effects occurring due to transport time variability (TTV) and to suggest a calculation model to estimate the value of transport time variability (VTTV). In order to validate the model and its usability it was successfully tested in a case study for a large Swedish retail company. The effects of delays can be divided into four main types: System Killers, Catastrophic Events, Expected Risks, and Contingencies, of which the last two are relevant for VTTV. The model applies these in a two-step cost function with a fixed and variable part, building on previous studies of VTW for passenger transport based on the scheduling utility approach. A main theoretical result is that the estimation of VTTV is derived mathematically independently of which measure that is chosen for the quantification of TTV.

  • 10.
    Antonsson, Hans
    et al.
    Swedish National Road and Transport Research Institute.
    Finnveden, Göran
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Gullberg, Anders
    Beser Hugosson, Muriel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Höjer, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Isaksson, Karolina
    Swedish National Road and Transport Research Institute.
    Kaijser, Arne
    Philosophy and History, KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, History of Science, Technology and Environment.
    Laestadius, Staffan
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics.
    Mattsson, Lars-Göran
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Nelldal, Bo-Lennart
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Summerton, Jane
    Swedish National Road and Transport Research Institute.
    Åkerman, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Nu finns chansen att riva upp beslutet om förbifarten2014In: Dagens nyheter, ISSN 1101-2447, no 2014-09-16Article in journal (Other (popular science, discussion, etc.))
  • 11.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Börjesson, M.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Eliasson, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Response to Wadud and Baierl: “Explaining ‘peak car’ with economic variables: An observation”2017In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 95, p. 386-389Article in journal (Refereed)
  • 12.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Habibi, Shiva
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Sundbergh, P.
    Evaluation of the Swedish car fleet model using recent applications2016In: Transport Policy, ISSN 0967-070X, E-ISSN 1879-310X, Vol. 49, p. 30-40Article in journal (Refereed)
    Abstract [en]

    The composition of the car fleet with respect to age, fuel consumption and fuel types plays an important role on environmental effects, oil dependency and energy consumption. In Sweden, a number of different policies have been implemented to support CO2 emission reductions. In order to evaluate effects of different policies, a model for the evolution of the Swedish car fleet was developed in 2006. The model has been used in a number of projects since then, and it is now possible to compare forecasts with actual outcomes. Such evidence is relatively rare, and we think it may be useful to share our experience in this respect.We give a brief overview of the Swedish car fleet model system. Then we describe policies that have been implemented in recent years and the evolution of the Swedish car fleet. We then focus on two projects which enable comparison with actual outcomes, and analyse the differences between forecasts and outcomes. We find that the model has weaknesses in catching car buyers' preferences of new technology. When this is not challenged too much, the model can forecast reasonably well on an aggregate level. We also find that the model is quite sensitive to assumptions on future supply. This is not so much related to the model, but to its use. Depending on the use of the forecasts - be it car sales, emissions or fuel demand - it may be necessary to use different supply scenarios to get an idea of the robustness of the forecast result.

  • 13.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Habibi, Shiva
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Sundbergh, Pia
    The Swedish Car Fleet Model: Evaluation of Recent ApplicationsManuscript (preprint) (Other academic)
  • 14.
    Blom Västberg, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Five papers on large scale dynamic discrete choice models of transportation2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Travel demand models have long been used as tools by decision makers and researchers to analyse the effects of policies and infrastructure investments. The purpose of this thesis is to develop a travel demand model which is: sensitive to policies affecting timing of trips and time-space constraints; is consistent with microeconomics; and consistently treats the joint choice of the number of trips to perform during day as well as departure time, destination and mode for all trips. This is achieved using a dynamic discrete choice model (DDCM) of travel demand. The model further allows for a joint treatment of within-day travelling and between-day activity scheduling assuming that individuals are influenced by the past and considers the future when deciding what to do on a certain day.

    Paper I develops and provides estimation techniques for the daily component of the proposed travel demand model and present simulation results provides within sample validation of the model. Paper II extends the model to allow for correlation in preferences over the course of a day using a mixed-logit specification. Paper III introduces a day-to-day connection by using an infinite horizon DDCM. To allow for estimation of the combined model, Paper III develops conditions under which sequential estimation can be used to estimate very large scale DDCM models in situations where: the discrete state variable is partly latent but transitions are observed; the model repeatedly returns to a small set of states; and between these states there is no discounting, random error terms are i.i.d Gumble and transitions in the discrete state variable is deterministic given a decision.

    Paper IV develops a dynamic discrete continuous choice model for a household deciding on the number of cars to own, their fuel type and the yearly mileage for each car. It thus contributes to bridging the gap between discrete continuous choice models and DDCMs of car ownership.

    Infinite horizon DDCMs are commonly found in the literature and are used in, e.g., Paper III and IV in this thesis. It has been well established that the discount factor must be strictly less than one for such models to be well defined.Paper V show that it is possible to extend the framework to discount factors greater than one, allowing DDCM's to describe agents that: maximize the average utility per stage (when there is no discounting); value the future greater than the present and thus prefers improving sequences of outcomes implying that they take high costs early and reach a potential terminal state sooner than optimal.

  • 15.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, Superseded Departments (pre-2005), Infrastructure and Planning.
    A joint between-day and within-day activity based travel demand with forward looking individualsManuscript (preprint) (Other academic)
    Abstract [en]

    Including day-to-day planning to account for systematic variability in activity participation has the potential to further improve travel demand models. This paper introduce a dynamic discrete choice model of day-to-day and within-day planning in a joint framework. No model up to date jointly treats within-day and day-to-day planning with individuals that take future days into account. The model is estimated using a combination of a small survey with week long data and a larger single day travel survey. A static, myopic and forward looking version of the model is estimated. There is a big improvement in model fit when moving from a static to a dynamic model, but allowing forward-looking behaviour gives a relatively small additional improvement. As a policy test, grocery stores are closed on Sundays. The myopic model predicts that people as a consequence will shop more on Mondays-Thursdays and therefore unintuitively also less on Saturdays. The forward looking model also predicts increased shopping on weekdays but mainly that people will shop more on Saturdays anticipating that stores are closed on Sundays.

  • 16.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, Superseded Departments (pre-2005), Infrastructure and Planning. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Discount factors greater than or equal to one in infinite horizon dynamic discrete choice modelsManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper, the theory on infinite horizon DDCM's is extended to allow for discount factors greater than or equal to one. The proposed methods are applied to Rust's (1987) bus engine replacement model, where a discount factor of 1.075 is identified using grid search. The infinite horizon problem with and without a terminal state are treated separately. Sufficient conditions are given for the existence of solutions to Bellman's equation in the terminal state problem and to a normalized version of Bellman's equation in the non-terminal state setting. If a terminal state exists, acting according to Bellman's equation still yields the maximum expected total utility under derived conditions on the one-stage utility functions and reachability of the terminal state. In the non-terminal state problem, $\beta=1$ implies that individuals maximize the average cost per stage, but for $\beta>1$ no rationale for acting according to Bellman's equation, even when it has a solution, has been found.

  • 17.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Jonsson, R. Daniel
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    A dynamic discrete choice activitybased travel demand modelManuscript (preprint) (Other academic)
    Abstract [en]

    During the last decades, many activity-based models have been developed in the literature. However, especially in random utility based models timing decisions are often treated poorly or inconsistently with other choice dimensions. In this paper we show how dynamic discrete choice can be used to overcome this problem. In the proposed model, trip decisions are made sequentially in time, starting at home in the morning and ending at home in the evening. At each decision stage, the utility of an alternative is the sum of the one-stage utility of the action and the expected future utility in the reached state.

    The model generates full daily activity schedules with any number of trips that each is a combination of one of 6 activities, 1240 locations and 4 modes. The ability to go from all to all locations makes evaluating the model very time consuming and sampling of alternatives were therefore used for estimation. The model is estimated on travel diaries and simulation results indicates that it is able to reproduce timing decisions, trip lengths and distribution of the number trips within sample.

    To explain when people perform different activities, two sets of parameters are used: firstly, the utility of being at home varies depending on the time of day; and secondly, constants determine the utility of arriving to work at specific times. This was enough to also obtain a good distribution of the starting times for free-time activities.

  • 18.
    Börjesson, Maria
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Fung, Chau Man
    Proost, Stef
    Optimal prices and frequencies for buses in Stockholm2017In: Economics of Transportation, ISSN 2212-0122, E-ISSN 2212-0130, Vol. 9, p. 20-36Article in journal (Refereed)
    Abstract [en]

    Many public transport services are heavily subsidized. One of the main justifications is the expected beneficial effect on road congestion. Stockholm introduced congestion pricing in 2006 and the effects on car and public transport demand were carefully monitored. The change in prices provides unique estimates on price-and cross-price elasticities. This paper uses these data to model how the optimal pricing, frequency, bus size and number of bus lanes for a corridor depends on the presence of congestion pricing for cars. Results show that the presence of road pricing makes the current subsidies for peak bus trips too high. However, the major welfare benefits of re-optimizing the current bus supply stem from a decrease in frequencies during the off-peak period and the use of larger buses.

  • 19.
    Börjesson, Maria
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Jonsson, R. Daniel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Berglund, Svante
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Almstrom, Peter
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System analysis and economics. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Land-use impacts in transport appraisal2014In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 47, p. 82-91Article in journal (Refereed)
    Abstract [en]

    Standard cost-benefit analysis (CBA) does not take into account induced demand due to relocation triggered by infrastructure investments. Using an integrated transport and land-use model calibrated for the Stockholm region, we explore whether this has any significant impact on the CBA outcome, and in particular on the relative ranking of rail and road investments. Our results indicate that induced demand has a larger impact on the benefit of rail investments than on the benefit of road investments. The effect on the relative ranking is still limited for two reasons. First, the number of houses that are built over 20 30 years is limited in comparison to the size of the existing housing stock. Second, the location of most of the new houses is not affected by any single infrastructure investment, since the latter has a marginal effect on total accessibility in a city with a mature transport system. A second aim of this paper is to investigate the robustness of the relative CBA ranking of rail and road investments, with respect to the planning policy in the region 25 years ahead. While the results suggest that this ranking is surprisingly robust, there is a tendency that the net benefit of rail investments is more sensitive to the future planning policy than road investments. Our results also underscore that the future land-use planning in the region in general has a considerably stronger impact on accessibility and car use than individual road or rail investments have.

  • 20.
    Chen, Xi
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System analysis and economics.
    How the free public transport policy affects the travel behavior of individual: A case study in Tallinn2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 21.
    Chengxi, Liu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Anders, Karlström
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Estimating changes in transport CO2 emissions due to changes in weather and climate in SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    There is a considerable body of studies on the relationship between daily transport activities and CO2 emissions. However, how these emissions vary in different weather conditions within and between the seasons of the year is largely unknown. Because individual activity–travel patterns are not static but vary in different weather conditions, it is immensely important to understand how CO2 emissions vary due to the change of weather. Using Swedish National Travel Survey data, with emission factors calculated through the European emission factor model ARTEMIS, this study is a first attempt to derive the amount of CO2 emission changes subject to the change of weather conditions. A series of econometric models was used to model travel behaviour variables that are crucial for influencing individual CO2 emissions. The marginal effects of weather variables on travel behaviour variables were derived. The results show an increase of individual CO2 emissions in a warmer climate and in more extreme temperature conditions, whereas increasing precipitation amounts and snow depths show limited effects on individual CO2 emissions. It is worth noting that the change in CO2 emissions in the scenario of a warmer climate and a more extreme temperature tends to be greater than the sum of changes in CO2 emissions in each individual scenario. Given that a warmer climate and more extreme weather could co-occur more frequently in the future, this result suggests even greater individual CO2 emissions than expected in such a future climate.

  • 22.
    Chengxi, Liu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Anders, Karlström
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Weather Variability and Travel Behaviour - What Do We Know and What Do We Not KnowManuscript (preprint) (Other academic)
    Abstract [en]

    Given that severe weather conditions is becoming more and more frequent, understanding the roles of weathers in influencing individual’s daily activity-travel pattern is important. Whilst some of previously rare events, such as heavy rain, unpredictable snow, higher temperature, less clear differences between seasons etc., would become more common, it is still largely unknown how individual would change and adapt their travel pattern in future climate conditions. Because of this concern, the number of researches on weather and travel behaviour has been increased dramatically in the recent decades. Most of those empirical evidences, however, have not been adopted in cost-benefit analysis (CBA), which serves as the main tool for policy evaluation and project selection by stakeholders. This study summarizes the existing findings in relations between weather variability and travel behaviour, and critically assesses the methodological issues in those studies. Several further research directions are identified and suggested for bridging the gap between empirical evidence and current practice in CBA.

  • 23.
    Chengxi, Liu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Jointly modelling individual’s daily activity-travel time use andmode share by a nested multivariate Tobit model system2015In: Transportation Research Procedia: 21st International Symposium on Transportation and Traffic Theory, Elsevier, 2015, Vol. 9, p. 71-89Conference paper (Refereed)
    Abstract [en]

    Understanding mechanisms underlie the individual’s daily time allocations is very important to understand the variability ofindividual’s time-space constraints and to forecast his/her daily activity participation. At most of previous studies, activity timeallocation was viewed as allocating a continuous quantity (daily time budget) into multiple discrete alternatives (i.e. variousactivities and trips to engage with). However, few researches considered the influence of travel time that needs to be spent onreaching the activity location. Moreover, travel time itself is influenced by individuals’ mode choice. This can lead to an over- orunder-estimation of particular activity time location. In order to explicitly include the individual’s travel time and mode choiceconsiderations in activity time allocation modelling, in this study, a nested multivariate Tobit model is proposed. This proposedmodel can handle: 1. Corner solution problem (i.e. the present of substantial amount of zero observations); 2. Time allocationtrade-offs among different types of activities (which tends to be ignored in previous studies); 3. Travel is treated as a deriveddemand of activity participation (i.e. travel time and mode share are automatically censored, and are not estimated, ifcorresponding activity duration is censored). The model is applied on a combined dataset of Swedish national travel survey(NTS) and SMHI (Swedish Meteorological and Hydrological Institute) weather record. Individuals’ work and non-work activitydurations, travel time and mode shares are jointly modelled as dependent variables. The influences of time-locationcharacteristics, individual and household socio demographics and weather characteristics on each dependent variable areexamined. The estimation results show a strong work and non-work activity time trade-offs due to the individual’s time-spaceconstraints. Evidences on a potential positive utility of travel time added on non-work activity time allocation in the Swedish case,are also found. Meanwhile, the results also show a consistent mode choice preference for a given individual. The estimatednested multivariate Tobit model provides a superior prediction, in terms of the deviation of the predicted value against the actualvalue conditional on the correct prediction regarding censored and non-censored, compared to mutually independent Tobitmodels. However, the nested multivariate Tobit model does not necessarily have a better prediction for model componentsregarding non-work related activities.

  • 24.
    Dharmowijoyo, Bayu Endrayana
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Susilo, Yusak O
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Adiredja, L. S.
    Collecting a multi-dimensional three-weeks household time-use and activity diary in the Bandung Metropolitan Area, Indonesia2015In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 80, p. 231-246, article id 1641Article in journal (Refereed)
    Abstract [en]

    This paper describes a comprehensive panel data collection and analysis at household level, including detailed travel behaviour variables and comprehensive in-home and out-of-home activities, individual cognitive habits and affective behaviours, the rate of physical activity, as well as health related quality of life (QoL) information in the Bandung Metropolitan Area (BMA) of Indonesia. To our knowledge, this is the first attempt to collect an individual's activity diary over an extended period as it captures the multi-tasking activities and multidisciplinary factors that underlie individual activity-travel patterns in a developing country. Preliminary analyses of the collected data indicate that different beliefs, anticipated emotions, support and attachment to motorised modes significantly correlate with different groups of occupation, gender, age, activity participation, multi-tasking activities, and physical health, but not with different social and mental health. This finding highlights the reason why implementing car reduction policies in Indonesia, without breaking or changing the individual's habits and influencing his/her attitudes have not been fruitful. The results also show that endorsing more physical activities may result in a significant reduction in the individual's motorised mode use, whilst individuals who demonstrate a tendency to use their spare time on social activities tend to have better social health conditions. Furthermore, undertaking multi-tasking out-of-home discretionary activities positively correlates with better physical health. All these highlight the importance of properly understanding and analysing the complex mechanisms that underlie these fundamental factors that shape individual daily activity-travel patterns in developing countries. This type of multidisciplinary approach is needed to design better transport policies that will not only promote better transport conditions, but also a healthier society with a better quality of life.

  • 25. Dharmowijoyo, Dimas B. E.
    et al.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Relationships among discretionary activity duration, its travel time spent and activity space indices in the Jakarta Metropolitan Area, Indonesia2016In: Journal of Transport Geography, ISSN 0966-6923, E-ISSN 1873-1236, Vol. 54, p. 148-160Article in journal (Refereed)
    Abstract [en]

    This study examines the interdependencies among an individual's time allocation for different activities and the travel time spent on a given day, socio-demographic and built environment variables on these in-home and out of-home discretionary activities time duration, and how interaction of those variables on discretionary activities time duration influences an individual's activity space indices in the Jakarta Metropolitan Area (JMA), Indonesia. The 3SLS model and the 2004 SITRAMP household travel survey were used to achieve this objective. The results show that the time allocation for certain discretionary activities significantly influences the time allocation for other discretionary activities. Workers, students and non-workers have different complex mechanisms pertaining to how they allocate time across different activities and journeys. This unique trade-off mechanism gives an individual a unique distribution of activity locations and spatial movement patterns. This is observed via his/her activity space indices throughout time and space. For example, the estimation result shows that workers' and students' time-use allocation, activities participation and activity space indices are highly influenced by their engagement in mandatory activities. However, this is not the case for non-workers. Furthermore, the mandatory travel time variable has a stronger impact on an individual's discretionary activities time-use pattern than the duration of mandatory activities. This may lead to the argument that, in order to provide more opportunities and flexibilities among the JMA's workers and students for undertaking discretionary activities, travel time reduction policies can play more significant role in shaping the discretionary activity-travel patterns than reduction in working/school hour policies. Additionally, in-line with previous findings in developed countries, locating grocery shops closer to residential areas in the CBD and in suburban areas creates more opportunities for workers and students to spend more time on out-of-home maintenance activities; with a shorter travel time, especially on. Fridays.

  • 26.
    Dharmowijoyo, Dimas B. E.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Analysing the complexity of day-to-day individuals’ activity-travel pattern using Multi-dimensional Sequence Alignment Method: A case study in Bandung Metropolitan Area, IndonesiaManuscript (preprint) (Other academic)
  • 27.
    Dharmowijoyo, Dimas B. E.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    On complexity and variability of individuals’ day-to-day discretionary activitiesManuscript (preprint) (Other academic)
  • 28.
    Dharmowijoyo, Dimas B. E.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Relationships among discretionary activity duration, travel time spent and activity space indices in the Jakarta Metropolitan Area, IndonesiaManuscript (preprint) (Other academic)
  • 29. Ekström, J.
    et al.
    Engelson, Leonid
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Rydergren, C.
    Towards optimal locations and toll levels in congestion pricing schemes2009In: 16th ITS World Congress, World Congress on Intelligent Transport Systems (ITS), 2009Conference paper (Refereed)
    Abstract [en]

    This paper addresses the problem of designing a road congestion pricing scheme with link tolls. The problem involves decisions on where to locate the toll collecting facilities and what tolls to charge the road users. We formulate this problem as a bi-level program, with the objective to maximize the net social surplus, which include the cost of setting up and operate the toll collection system. A previously developed heuristic method is applied to find close to optimal toll locations and charges for a traffic network representing the Stockholm region. The result is compared with the current congestion pricing scheme in Stockholm.

  • 30. Ettema, Dick
    et al.
    Fernandez Abenoza, Roberto
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Octavius Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Satisfaction with intermodal trips in Stockholm: How do service attributes influence satisfaction with the main mode and with the journey as a whole?2016In: TRB 95th Annual Meeting Compendium of Papers, 2016, Vol. 16, article id 2247Conference paper (Other academic)
    Abstract [en]

    Using door-to-door travel satisfaction data which was collected in Stockholm, Sweden, in this paper the authors have investigated how satisfaction with the main mode is related to the overall trip satisfaction, and how service related variables influence satisfaction at both levels. The results show that every stages within the journey matters in influencing traveler’s door-to-door journey experience. Some other factors, such as occurrence of disruptions, were also found as significant factor influencing the reported travel satisfaction. The quality of vehicle design, one of the traditional emphases in improving passenger’ travel satisfaction, affects the trip as a whole but not the main mode satisfaction. This indicates that this variable is more relevant for the access and egress trips made by addition means of public transport. Overall, the authors' findings suggest that in order to improve the overall trip satisfaction, it does not suffice to focus only on characteristics of the main mode, but also the quality of egress and access trips and also the quality of the interchanges as a whole.

  • 31.
    Fadaei, Masoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    TU Delft, The Netherlands.
    An empirical evaluation of measures to improve bus service reliability: Performance metrics and a case study in Stockholm2015Conference paper (Other academic)
    Abstract [en]

    This paper evaluates the effects of implementation of a range of physical and operational measures during a pilot study on the busiest and most frequent trunk bus line in Stockholm, Sweden. Vehicle positioning and passenger counts data were analysed to evaluate the impact of the field experiment. The study has proven that the bus service performance has been improved from both passengers and operator perspectives. These measures resulted with a service that is 7% faster on average yielding a 10% decrease in passenger in-vehicle times. The faster service leads to 8 minutes shorter cycle time which could potentially cut the fleet size by 2 buses. The results demonstrate that improved regularity and less bunching leading to a 25% reduction in passengers’ waiting times due to irregularity. However, no apparent change in dwell times has been observed. We estimate that each passenger saved 2 minutes which is 10% of journey time. These time savings amount to 9 million Swedish Crowns (1.1 million USD) per year for weekday afternoon peak periods only. 

  • 32.
    Fadaei, Masoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    Delft University of Technology, Netherland..
    Evaluating the Performance and Benefits of Bus Priority, Operation and Control Measures2016In: Proceedings of the 95th Transportation Research Board Annual Meeting, Washington DC., 2016Conference paper (Refereed)
    Abstract [en]

    Preferential measures are designed and implemented to improve public transport performance and level-of-service. In the case of urban bus systems, priority, operational and control measures are aimed to elevate bus services to buses with high level of service (BHLS). Even though there is an explosive growth in preferential measures implementation and growing research interest in investigating their impact on performance indicators, there is lack of a systematic evaluation of their benefits. We present an evaluation framework and a detail sequence of steps for quantifying the impacts of public transport preferential measures. The effects of service performance on travel times and costs are assessed by accounting for relations between reliability and waiting times, crowding and perceived travel times, and vehicle scheduling and operational costs. The evaluation integrates the implications of reliability on generalized passenger travel costs and operational costs. We deploy the proposed evaluation framework to a field experiment in Stockholm where a series of measures were implemented on the busiest bus line. The results suggest that the total passenger and operator benefits amount to 47 million Swedish crowns on an annual basis. The overall assessment of the impacts of preferential measures enables the comparison of different implementations, assess their effectiveness, prioritize alternative measures and provide a sound basis for motivating investments.

  • 33.
    Fadaei, Masoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    Delft University of Technology - TU Delft, Netherlands.
    Rolling Horizon Predictions of Bus Trajectories2014In: OPT-i 2014 - 1st International Conference on Engineering and Applied Sciences Optimization, Proceedings, 2014, p. 875-886Conference paper (Refereed)
    Abstract [en]

    Bus travel times are subject to inherent and recurrent uncertainties. A real-time prediction scheme regarding how the transit system evolves will potentially facilitate more adaptive operations as well as more adaptive passengers’ decisions. This scheme should be tractable, sufficiently fast and reliable to be used in real time applications. For this purpose, a heuristic hybrid scheme for departure time estimation is proposed in this study. The prediction generated by the proposed hybrid scheme consists of three travel time components: schedule, instantaneous and historical data sources. Genetic algorithm is applied in order to specify the contribution of each data source component to the prediction scheme. The proposed scheme was applied for a trunk bus line in Stockholm, Sweden. In addition, the currently deployed scheme was replicated in order to compare the performance of both schemes. The results suggest that the proposed scheme reduces the overall mean absolute error by almost 20%. Moreover the proposed scheme provides better predictions except for very long term predictions where both schemes yield the same performance. 

  • 34.
    Fadaei, Masoud
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. Delft University of Technology, Netherland.
    Bhaskar, Ashish
    Smart Transport Research Centre, School of Civil Engineering and Built Environment, Queensland University of Technology (QUT), Australia.
    A Hybrid Scheme for Real-Time Prediction of Bus TrajectoriesManuscript (preprint) (Other academic)
    Abstract [en]

    The uncertainty associated with public transport services can be partially counteracted by developing real-time models to predict downstream service conditions. In this study, a hybrid approach for predicting bus trajectories by integrating multiple predictors is proposed. The prediction model combines schedule, instantaneous and historical data. The contribution of each predictor as well as values of respective parameters is estimated by minimizing the prediction error using a linear regression based heuristic. The hybrid method was applied to five bus lines in Stockholm, Sweden and Brisbane, Australia. The results indicate that the hybrid method consistently outperforms the timetable and delay conservation prediction method for different line layouts, passenger demands and operation practices. Model validation confirms model transferability and real-time applicability. Generating more accurate predictions can help service users adjust their travel plans and service providers to deploy proactive management and control strategies to mitigate the negative effects of service disturbances.

  • 35.
    Fadaei Oshyani, Masoud
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    New Opportunities in Urban Transport Data: Methodologies and Applications2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The deployment of Information and Communication Technologies (ICT) is growing in transportation which may contribute to a more efficient and effective service. The data acquired from ICT based systems could be used for many purposes such as statistical analysis and behavior learning and inference. This dissertation addresses the question of how transportation data that was collected for a specific application can be used for other applications. This thesis consists of five separate papers, each addressing a subset of the topic.

    The first paper estimates a route choice model using sparse GPS data. This paper demonstrates the feasibility of an Indirect Inference based estimator in a model with random link costs, allowing for a natural correlation structure across paths, where the full choice set is considered.

    The second paper presents an estimator for the mean speed and travel time at network level based on indirect inference when the data are spatially and temporally sparse.

    The third paper proposes an evaluation framework which outlines a systematic process to quantify and assess the impacts of public transport preferential measures on service users and providers in monetary terms, using public transport data sources.

    In the fourth and fifth papers, a methodology is developed and implemented for integrating different prediction models and data sources while satisfying practical requirements related to the generation of real-time information. Then the performance of the proposed prediction method is compared with the prediction accuracy obtained by the currently deployed methods.

  • 36.
    Fernandez Abenoza, Roberto
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. TU Delft.
    Octavius Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    How does travel satisfaction sum up?: Decomposing the door-to-door experience for multimodal tripsManuscript (preprint) (Other academic)
    Abstract [en]

    Understanding how satisfaction with individual trip legs aggregates to the overall travel experience for different types of trips will enable the identification of the trip legs that are most impactful. For this purpose we analyze data on retrospective evaluations of entire multi-modal trip experiences and satisfaction with individual trip legs. We formulate and describe alternative aggregation rules and underpin them in theory and previous empirical findings. The results of a series of regression models show that for a large number of multi-modal trip configurations normative rules can better reproduce overall travel satisfaction than heuristic rules. This indicates that all trip legs need to be considered when evaluating the overall travel experience, especially for trips legs involving waiting and/or transferring time. In particular, weighting satisfaction with individual trip legs with perceived trip leg durations yielded the best predictor of overall travel satisfaction. No evidence for a disproportional effect of the last or most exceptional part of the trip was found. This research contributes to the literature on combining multi-episodic experiences and provides novel empirical evidence in the transport domain. 

  • 37.
    Fernandez Abenoza, Roberto
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. Delft University of Technology, Netherlands.
    Susilo, Yusak Octavius
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Travel satisfaction with public transport: Determinants, user classes, regional disparities and their evolution2017In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 95, p. 64-84Article in journal (Refereed)
    Abstract [en]

    Increasing public transport ridership while providing a service that better caters to individual travelers poses an important goal and challenge for society, particularly public transport authorities and operators. This study identifies and characterizes current and potential users of public transport in Sweden and identifies the most important determinants of travel satisfaction with Public Transport services for each segment of travelers. In addition, it investigates the changes over time of attribute importance among the different segments and the inter-segment geographical variation of overall satisfaction. The analysis is based on a dataset of almost half a million records. Travelers were clustered based on their socio-demographics, travel patterns and accessibility measures to enable the analysis of determinants of satisfaction for different market segments. The cluster analysis results with five segments of Swedish travelers include: (i) inactive travelers; (ii) long distance commuters; (iii) urban motorist commuters; (iv) rural motorist commuters and;(v) students. By contrasting satisfaction with the importance of each quality of service attribute, three key attributes that should be prioritized by stakeholders are identified: customer interface, operation, network and  length  of  trip time. Interestingly, the results suggest an overall similarity in the importance of service attributes among traveler segments. Nevertheless, some noticeable differences could be observed. The quality of service attributes’ importance levels reveal overall changes in appreciations and consumption goals over time. The more frequent public transport user segments are more satisfied across the board and are characterized by a more balanced distribution of attribute importance while rural motorist commuters are markedly dissatisfied with service operation attributes. This work can help authorities to tailor their policies to specific traveler groups.

  • 38.
    Fernández Abenoza, Roberto
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Improving Travel Satisfaction with Public Transport2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The existing link between PT travelers’ satisfaction, ridership and loyalty prove the relevance of improving overall trip satisfaction. The thesis present an array of approaches and methodologies aiming at increasing overall satisfaction with PT door-to-door trips while covering important issues that previous research has failed to address. These knowledge gaps include: disregarding the different needs and priorities of different type of travelers; overlooking the evolution over time and across geographical areas that overall satisfaction and satisfaction with specific service attributes may experience; and, neglecting the importance of access and egress legs.

    Based on the Swedish customer satisfaction barometer (2001-2013), an investigation of the determinants of PT satisfaction and their evolution over time (I) shows that: a) the deterioration of overall satisfaction with PT in Sweden in recent years is driven by a decrease in satisfaction with customer interface and length of trip time; b) these two service aspects as well as operation are found as key determinants of overall satisfaction which users consistently rate among the least satisfactory.

    The diversity of needs and priorities of SKT travelers was reduced into 5 distinctive multi-modal travelers’ groups (II). These travelers’ groups exhibited geographical disparities and an in between-groups overall similarity in the importance attached to the service attributes. Nevertheless, some noticeable differences could be observed. The service attributes’ importance levels reveal overall changes in appreciations and consumption goals over time.

    A number of both normative and heuristic satisfaction aggregation rules are tested on METPEX dataset for different types of trip configurations (III). The results show that normative rules can better reproduce overall travel satisfaction than heuristic rules, indicating that all trip legs need to be considered when evaluating the overall travel experience.

  • 39.
    Fernández Abenoza, Roberto
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System analysis and economics.
    Temporal and spatial variability of determinants of satisfaction with public transport in Sweden2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Measuring and analysing satisfaction with public transport services facilitates service performance

    monitoring, market analysis, benchmarking and the identification of priority areas. The systematic and

    regular collection of information concerning satisfaction enables to investigate how passengers’

    satisfaction as well as its determinants changes over time and space. These changes may be driven by

    changes in service quality or shifts in passengers’ expectations and preferences. This study analyses how

    satisfaction with public transport and its determinants evolved over time (in the years 2001-2013) and

    across space (in 5 county-regions) in Sweden. The determinants of satisfaction are identified based on a

    factor analysis and the estimation of multivariate satisfaction regression models. The superposition of the

    findings culminates in two dynamic passenger satisfaction priority maps which allow identifying priority

    areas based on observed trends in satisfaction with quality of service attributes and their respective

    importance. The deterioration of Overall Satisfaction with public transport in Sweden in recent years is

    driven by a decrease in satisfaction with Customer interface and Length of Trip Time. These two service

    aspects as well as Operation and Network were found key determinants of Overall Satisfaction which users

    from most of the county-regions consistently rate among the least satisfactory. The results of this thesis are

    instrumental in supporting service providers in designing measures that will foster satisfaction in the

    future.

  • 40.
    Flötteröd, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    A search acceleration method for optimization problems with transport simulation constraints2017In: Transportation Research Part B: Methodological, ISSN 0191-2615, Vol. 98, p. 1339-1351Article in journal (Refereed)
    Abstract [en]

    This work contributes to the rapid approximation of solutions to optimization problems that are constrained by iteratively solved transport simulations. Given an objective function, a set of candidate decision variables and a black-box transport simulation that is solved by iteratively attaining a (deterministic or stochastic) equilibrium, the proposed method approximates the best decision variable out of the candidate set without having to run the transport simulation to convergence for every single candidate decision variable. This method can be inserted into a broad class of optimization algorithms or search heuristics that implement the following logic: (i) Create variations of a given, currently best decision variable, (ii) identify one out of these variations as the new currently best decision variable, and (iii) iterate steps (i) and (ii) until no further improvement can be attained. A probabilistic and an asymptotic performance bound are established and exploited in the formulation of an efficient heuristic that is tailored towards tight computational budgets. The efficiency of the method is substantiated through a comprehensive simulation study with a non-trivial road pricing problem. The method is compatible with a broad range of simulators and requires minimal parametrization.

  • 41.
    Flötteröd, Gunnar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Osorio, C.
    Stochastic network link transmission model2017In: Transportation Research Part B: Methodological, ISSN 0191-2615, E-ISSN 1879-2367, Vol. 102, p. 180-209Article in journal (Refereed)
    Abstract [en]

    This article considers the stochastic modeling of vehicular network flows, including the analytical approximation of joint queue-length distributions. The article presents two main methodological contributions. First, it proposes a tractable network model for finite space capacity Markovian queueing networks. This methodology decomposes a general topology queueing network into a set of overlapping subnetworks and approximates the transient joint queue-length distribution of each subnetwork. The subnetwork overlap allows to approximate stochastic dependencies across multiple subnetworks with a complexity that is linear in the number of subnetworks. Additionally, the network model maintains mutually consistent overlapping subnetwork distributions. Second, a stochastic network link transmission model (SLTM) is formulated that builds on the proposed queueing network decomposition and on the stochastic single-link model of Osorio and Flötteröd (2015). The SLTM represents each direction of a road and each road intersection as one queueing subnetwork. Three experiments are presented. First, the analytical approximations of the queueing-theoretical model are validated against simulation-based estimates. An experiment with intricate traffic dynamics and multi-modal joint distributions is studied. The analytical model captures most dependency structure and approximates well the simulated network dynamics and joint distributions. Even for the considered simple network, which consists of only eight links, the proposed subnetwork decomposition yields significant gains in computational efficiency: It uses less than 0.0025% of the memory that is required by the use of a full network model. Second and third, the proposed SLTM is illustrated with a linear test network adopted from the literature and a more general topology network containing a diverge node and a merge node. Time-dependent probabilistic performance measures (occupancy uncertainty bands, spillback probabilities) are presented and discussed.

  • 42.
    Gkioulou, Zafeira
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Evaluating the impact of waiting time uncertainty on passengers´decisions2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Service reliability is one of the main factors influencing public transport level of

    service and, thus, passengers’ satisfaction. Public transport services are subject to

    various sources of uncertainty related to traffic conditions, public transport operations

    and passenger demand. Passengers are able to form their perception of trip attributes

    and service reliability through accumulating experiences of repetitive travel choices.

    Perceived service reliability can be improved either by increasing the ground-truth

    service reliability (e.g. introduce exclusive bus lanes, control strategies etc.) or by

    providing real time information (RTI) to passengers. However, RTI prediction

    schemes might not be perfectly accurate and thus, passengers might be able to account

    for the reliability of the provided information as well.

    The learning mechanism of individuals becomes, as a result, an important

    component in Dynamic Transit Assignment Models (DTAM) which enables

    accounting for how perceived reliability of service and the provided information

    evolves, through iterative network loading.

    This thesis provided the modeling framework for passengers’ perception of

    reliability and its effects on decision making with respect to path choice. Within-day

    effect is represented through the incorporation of scheduling constraints, while

    passengers’ learning mechanism accounts for updates in their expectations and the

    perceived level of information credibility in the day-to-day context.

    The proposed model was applied to Stockholm’s rapid transit network which was

    simulated in BusMezzo, an agent-based public transport assignment model. The

    application used the real-world timetables, vehicle schedules and RTI prediction

    scheme. Passengers’ learning function was analysed under various specifications

    which corresponded to different levels of adaptation.

    The results highlight the importance of capturing service uncertainty and the

    credibility associated with alternative information sources, while they stress the need

    for empirical estimation and validation of the proposed model. This study also

    provides the framework for future evaluation of measures which aim to improve

    service reliability.

  • 43. Glerum, Aurélie
    et al.
    Blom Västberg, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Frejinger, Emma
    Karlström, Anders
    Beser Hugosson, Muriel
    Bierlaire, Michel
    A dynamic discrete-continuous choice model of car ownership, usage and fuel typeManuscript (preprint) (Other academic)
    Abstract [en]

    This paper presents a dynamic discrete-continuous choice model of car ownership, usage, and fuel type that embeds a discrete-continuous choice model into a dynamic programming framework to account for the forward-looking behavior of households in the context of car acquisition. More specifically, we model the transaction type, the choice of fuel type, and the annual driving distance for up to two cars in the household. We present estimation and cross-validation results based on a subsample of the Swedish population that is obtained from combining the population and car registers. Finally we apply the model to analyze a hypothetical policy that consists of a subsidy that reduces the annual cost of diesel cars.

  • 44.
    Habibi, Habibi
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Frejinger, Emma
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Aggregation of alternatives and its influence on predictionManuscript (preprint) (Other academic)
    Abstract [en]

    In car type choice models, alternatives are usually grouped into categories by some of their main characteristics such as make, model, vintage, body type and/or fuel type. Each of these categories contains di erent versions of the cars that are usually not recognized in the applied literature. In this study we empirically investigate whether including the heterogeneity of these versions in the modeling does matter in estimation and prediction or not. We use detailed data on alternatives available on the market down to the versions level of each model, which enables us to account for heterogeneity in the model. We also have Swedish car registry data to represent demand. We estimate separate discrete choice models with diferent methods of correction for alternative aggregation, including nesting structure. These models are estimated based on year 2006 Swedish registry data for new cars, and predict for 2007. The results show that including heterogeneity of cars' versions in the model improves model tness but it does not necessarily improve prediction results.

     

  • 45.
    Habibi, Shiva
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Prediction-driven approaches to discrete choicemodels with application to forecasting car typedemand2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Models that can predict consumer choices are essential technical support fordecision makers in many contexts. The focus of this thesis is to address predictionproblems in discrete choice models and to develop methods to increase the predictivepower of these models with application to car type choice. In this thesis we challengethe common practice of prediction that is using statistical inference to estimateand select the ‘best’ model and project the results to a future situation. We showthat while the inference approaches are powerful explanatory tools in validating theexisting theories, their restrictive theory-driven assumptions make them not tailormadefor predictions. We further explore how modeling considerations for inferenceand prediction are different.Different papers of this thesis present various aspects of the prediction problemand suggest approaches and solutions to each of them.In paper 1, the problem of aggregation over alternatives, and its effects on bothestimation and prediction, is discussed. The focus of paper 2 is the model selectionfor the purpose of improving the predictive power of discrete choice models. Inpaper 3, the problem of consistency when using disaggregate logit models for anaggregate prediction question is discussed, and a model combination is proposedas tool. In paper 4, an updated version of the Swedish car fleet model is appliedto assess a Bonus-Malus policy package. Finally, in the last paper, we present thereal world applications of the Swedish car fleet model where the sensitivity of logitmodels to the specification of choice set affects prediction accuracy.

  • 46.
    Habibi, Shiva
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Beser Hugosson, Muriel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Sundbergh, Pia
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Evaluation of Bonus-Malus systems for reducing car fleet CO2 emissions in SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    Early 2014, an official Swedish government investigation report (FFF-report) was releasedproposing a policy package to promote a Fossil Free Fleet in Sweden by 2050. One objective ofthis policy package is to design a Bonus-Malus system that pushes the Swedish fleet compositiontowards the EU objectives of the average CO2 emissions of 95 g/km for new cars by 2021. Theproposed scenarios address cars bought by private persons as well as by companies. These scenariosdiffer in designs for registration tax, vehicle circulation tax, clean car premiums, company carbenefits tax and fuel tax. We use the Swedish car fleet model system to predict the effects of theproposed scenarios on the Swedish car fleet composition. Also, we build a simple supply model topredict future supply.Our model results show that none of the three proposed scenarios is actually successful enoughto meet the Swedish average CO2 emissions target of 95 g/km in 2020. The average CO2 emissionsin two of these scenarios are actually higher than in the business as usual scenario. Relative toa business as usual scenario the number of ethanol and gas cars is reduced in the other scenarioswhich is a negative result in terms of fossil fuel independence. Also, the Bonus-Malus system givesa positive net result in terms of budget effects showing that car buyers choose to pay the malus for acar with higher emissions rather than to be attracted by the bonus of a car with lower emissions.

  • 47.
    Habibi, Shiva
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Model combination for capturing the inconsistency in the aggregate predictionManuscript (preprint) (Other academic)
    Abstract [en]

    What is the appropriate aggregation level for modeling when the purpose of modelingis aggregate prediction: is it to estimate a disaggregate model and aggregateindividual predictions or estimate an aggregate model for the aggregate prediction?There is no unique answer to this old question in the literature as well as no generalmethodology to address the problem. In this paper, we propose to tackle theaggregation problem by employing and developing model combination methods tocombine aggregate and disaggregate models. Dierent aspects of aggregation arecovered in this paper: aggregation over time, individuals and alternatives. We examinethe eect of aggregation on the prediction accuracy of a nested multinomiallogit (NMNL). The application of interest is to predict the monthly share of cleancars in the Swedish car eet. We investigate a situation wherein the large scalemodels are already estimated, and we are interested in improving their predictionperformance in a post-processing manner. We combine NMNL with a regressiontree to capture individual heterogeneity as well as a time-series model to capturedynamics of the market share of clean cars at the aggregate level. Models are combinedthrough a latent variable model and a Bayesian model averaging approach.We propose aggregate likelihood as the likelihood to be maximized for the modelselection and combination when the purpose of modeling is aggregate prediction.The results show the increase in the predictive power of combined models.

  • 48.
    Habibi, Shiva
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Prediction-driven approach to model selection using feature selection and nonrandom hold-out validationManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper, we address the forecast problem and propose a prediction drivenapproach to model selection. Furthermore, we investigate to what extent dierentprediction questions lead to dierent \best" models. Most of the studies in theeld, take an inference-driven approach to select the best model and project theresults to the future population. In contrast, we take a prediction-driven approachfor both selection criteria and validation sample. We use feature (variable) selectionand nonrandom hold-out validation to select the model with the highest predictiveperformance in an out-of-sample prediction manner. The application of interest iscar type choice modeling using the Swedish car eet data. We introduce two dier-ent types of model selection criteria: maximum likelihood which is the conventionalmethod of model selection, and root mean squared error of the prediction quantityof interest. We compare the best models obtained by dierent criterion functions.The results show that the \best" model for the purpose of prediction depends con-siderably on the prediction question of interest. Moreover, when the objective isto predict a sub-section of a population such as the total share of ethanol cars,maximizing log-likelihood is not the most accurate model selection criterion.

  • 49. Hjorth, Katrine
    et al.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Engelson, Leonid
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Fosgerau, Mogens
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Estimating exponential scheduling preferences2015In: Transportation Research Part B: Methodological, ISSN 0191-2615, E-ISSN 1879-2367, Vol. 81, no 1, p. 230-251Article in journal (Refereed)
    Abstract [en]

    Different assumptions about travelers' scheduling preferences yield different measures of the cost of travel time variability. Only few forms of scheduling preferences provide non-trivial measures which are additive over links in transport networks where link travel times are arbitrarily distributed independent random variables: Assuming smooth preferences, this holds only for specifications with a constant marginal utility of time at the origin and an exponential or affine marginal utility of time at the destination. We apply a generalized version of this model to stated preference data of car drivers' route and mode choice under uncertain travel times. Our analysis exposes some important methodological issues related to complex non-linear scheduling models: One issue is identifying the point in time where the marginal utility of being at the destination becomes larger than the marginal utility of being at the origin. Another issue is that models with the exponential marginal utility formulation suffer from empirical identification problems. Though our results are not decisive, they partly support the constant-affine specification, in which the value of travel time variability is proportional to the variance of travel time.

  • 50. Jirsa, Vojtech
    et al.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Estimating the Hourly Variability of  Bicycle Trip Paterns and Characteristisc  from Automatic Bicycle Counters: Case Study In Prague, Czech Republic2016In: Proceedings of The Third International Conference on Traffic and Transport Engineering (ICTTE), Scientific Research Center , 2016, p. 769-776Conference paper (Refereed)
    Abstract [en]

    Nowadays it is common for many cities around the world to use automatic bicycle counters laid at main road segments to monitor the cyclists' traffic flow at any given time in the given location. In most cases, this data is then used to identify the peak period of the bicycle traffic. This paper introduces a method to classify the characteristics of bicycle traffic flows and inferring different proportion trip purposes based on the variations of hourly counts. Whilst of many previous studies investigated the key determinants of bicycle travel demand detected by these counters, none of these studies tried to distinguish different portions of different traffic characteristics in each counting section. In most cases the trip purposes of cycling were grouped into either prevailing utilitarian or prevailing recreational. In reality, however, these recorded bicycle traffic contains both trip purposes. The method which is introduced in this paper was developed and tested on the longitudinal datasets obtained from the bicycle counting system in the city of Prague over five years' period, i.e. 2010 to 2015. The system consists of 26 counting facilities in various city quarters covering wide variety of road segments. In achieving the study objective, first, a theoretical assumption was done to differentiate three different basic traffic characteristics and their respective hourly variations, i.e.: utilitarian, recreational affected by workhours, and recreational not affected by workhours. These hypothetical hourly variations were tested and confirmed based on the observed Prague sample. Obtained results were discussed with respect to geographical location, built environment and knowledge of local situation. The hourly variations of the recorded bicycle flow were influenced by the build environment factors such as specific land use in the proximity of counting section. The results also indicate some specific routes (and its direction) preferences.

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