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  • 1. Aakjer Nielsen, Michael
    Accidents on rural roads in Denmark2000Rapport (Annet (populærvitenskap, debatt, mm))
  • 2. Aakjer Nielsen, Michael
    et al.
    Greibe, Poul
    Signing and marking of substandard horizontal curves on rural roads1998Rapport (Annet (populærvitenskap, debatt, mm))
  • 3.
    Abadir Guirgis, Georg
    Linköpings Universitet.
    Ecodriving på SJ: förarperspektiv på tekniska hjälpmedel för beslutsfattande och utbildning i Ecodriving2013Rapport (Annet vitenskapelig)
    Abstract [sv]

    Trots att samtliga resor med SJs tåg i Sverige är märkta med Bra Miljöval skärps kraven på minskade utsläpp och energianvändning efter hand, varför SJ ständigt måste utveckla sin miljöprofil. På SJ har man därför arbetat fram en utbildning i energieffektiv körning (Ecodriving) samt låtit vissa av sina förare använda ett tekniskt hjälpmedel som stödjer detta, för att påvisa möjligheten till energibesparingar. Denna rapport tar upp två studier vilka är SJs försöksverksamhet inklusive en kritisk granskning av denna samt en kompletterande studie i form av observationer av utbildning i Ecodriving och intervjuer med förare. Resultaten av SJs försöksverksamhet är värdefulla och talar för att energibesparingar är genomförbara. Samtidigt så finns det en hel del osäkerhet i de energimätningsdata som samlats in varför det är svårt att dra några definitiva slutsatser. Resultatet av intervjuerna med förarna talar för att det finns en hel del oklarheter kring vilka risker och konsekvenser ett framtida införande av det tekniska hjälpmedlet för Ecodriving faktiskt innebär. Sammantaget finns anledning att genomföra fortsatta studier av hur man på bästa sätt kan införa energieffektiv körning av spårtrafik i sin helhet.

  • 4.
    Abadir Guirgis, Georg
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Lärarperspektiv på riskutbildningen för motorcyklister2011Rapport (Annet vitenskapelig)
    Abstract [en]

    Over the last decade it has become increasingly popular to ride a motorcycle in Sweden. A mandatory risk education for competence A and A1 was introduced from the 1st of November 2009. Since the education is new, few evaluations have been conducted so far.

    This study evaluates the risk education for motorcyclists based on the perspective of driving instructors. The goal was to compile the instructors' comments and experiences with respect to the new risk training. An additional objective was to examine the driving instructors' perceived effects of the education on their students' driving behavior. Six semi-structured interviews with driving instructors and an observational study of the education at various driving schools were conducted. In addition, a participant observation study was performed during a further education of 15 driving instructors. The results show that the instructors experience a great need for the new risk training and that the implementation of the training itself has been good. Students have been referring to the risk training, which according to the instructors indicate that the students have embraced the essence of the training. As a result, the students drive more carefully now and think twice in certain situations according to the instructors. This was considered a desirable result.

  • 5.
    Abadir Guirgis, Georg
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Peters, Björn
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Simulatorbaserad utbildning i ERTMS: utvärdering av utbildning och träning för lokförare i VTI:s tågsimulator2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Detta notat presenterar en studie för att utvärdera VTI:s tågsimulator för träning och utbildning i ERTMS (European Rail Traffic Management System) för lokförare. Resultaten visar att både lärare och elever är mycket positiva till den simulatorbaserade träningen och mycket tyder på att teori och simulatorträning som varvas ger bäst resultat. På sikt ska de större järnvägsstråken i Sverige utrustas med ERTMS. Detta kommer kräva stora utbildningsinsatser för Sveriges cirka 3 500 lokförare. Det är orealistiskt att dessa ska utbildas på riktiga spår och det finns ett behov av en mer realistisk ERTMS-simulator än den ERSA-simulator som Trafikverket erbjuder idag. Studiens syfte var därför att utvärdera VTI:s tågsimulator, dels jämfört med European Rail Software Applications (ERSA) simulatorn, dels för att studera två olika sätt att kombinera teoretisk utbildning med praktisk träning i simulator. Tre olika grupper jämfördes: Teoretisk utbildning i ERTMS kombinerat med träning i ERSA-simulator (grupp 0), teoretisk utbildning i ERTMS som avslutades med träning i VTI-simulatorn (grupp 1) och teoretisk utbildning i ERTMS som till viss del varvades med träning i VTI-simulatorn (grupp 2). Grupp 1 och 2 fick avsluta utbildningen med ett teoretiskt prov och ett praktiskt körprov i simulator. Grupp 0 endast fick göra det teoretiska provet.

  • 6.
    Abadir Guirgis, Georg
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Peters, Björn
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Lidström, Mats
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Fordonsteknik och simulering, FTS.
    Lokförarutbildning i Sverige: simulatoranvändning och ERTMS2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    Detta notat ger en översiktlig bild av den obligatoriska grundutbildningen till lokförare i Sverige och belyser i vilken mån simulatorbaserad träning förekommer inom utbildningen. Rapporten visar vilka möjligheter och begränsningar som finns med att öka användningen av simulatorer i lokförarutbildningen, samt beskriver de viktigaste styrdokumenten för lokföraryrket och lokförarutbildningen. Vidare presenteras Transportstyrelsens utbildningsplan för förarbevis och de aktörer som bedriver grundutbildning, fortbildning och examination. Trafikverkets E-Learning för ERTMS, ERSA-simulatorn samt operatörsspecifika ERTMS-utbildningar vid SJ och Green Cargo beskrivs. Forskarna har dessutom undersökt svenska tågoperatörers och utbildares nuvarande användning och framtida behov av simulatorer för grund- och fortbildning av lokförare. Exempel från andra domäner där simulatorer används i utbildningssammanhang lyfts också fram i rapporten.

  • 7.
    Abate, Megersa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Determinants of Capacity Utilisation in Road Freight Transportation2014Inngår i: Journal of Transport Economics and Policy, ISSN 0022-5258, E-ISSN 1754-5951, Vol. 48, s. 137-152Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recent performance indicators in the European road freight transport sector show there is an excess capacity. To shed light on this, this paper studies two aspects of capacity utilisation in trucking: the extent of empty running and the load factor. Using a joint econometric modelling framework, the paper shows that they can be explained as a function of haul, carrier, and truck characteristics. For estimation, a unique dataset from the Danish heavy vehicle trip diary was used. The results indicate distance and being a for-hire carrier have a positive effect on capacity utilisation, whereas the effect of truck size is non-linear.

  • 8.
    Abate, Megersa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Does fuel price affect trucking industry’s network characteristics?: evidence from Denmark2014Rapport (Annet vitenskapelig)
    Abstract [en]

     The 2000s were dominated by rising fuel prices and economic recession. Both had an impact on the structure of the trucking industry and how freight was moved. This paper examines how fuel prices shaped trucking industry’s network characteristics such as the average length of haul, average load, and capacity utilization. In particular, we show the effect of fuel price on average length of haul using 29 quarterly independent surveys from the Danish heavy goods vehicle (HGV) trip diary from 2004 to 2011. The results show that the average length of haul is sensitive to changes in fuel price: a DKK 1 (0.18$) increase in diesel price/liter leads to a 4 percent decrease in the average length of haul in the 2004-2007 period. This implies that firms improve transport efficiency by reducing the number of kilometers needed to transport a tonne of cargo as a short run response to fuel price increases. This result, however, is not confirmed for the years following the 2008 financial crisis. It also depends on where in the distribution of the average length of haul one looks.

  • 9.
    Abate, Megersa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Economic effects of air transport market liberalization in Africa2016Inngår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 92, s. 326-337Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although the aviation industry is increasingly becoming important for Africa's economic development and integration, the ability of airlines to access foreign markets remains hindered by restrictive regulatory policies. Attempts have been made to fully liberalize the intra-African air transport market. Except for general assertions about the merits/demerits of liberalization, our empirical understanding of the welfare effects of such polices in Africa remains rudimentary. This study empirically measures the economic effects of air transport liberalization, mainly on two supply side variables: fare and service quality, measured as departure frequency. The empirical models evaluate how air fares and departure frequency respond to measures of openness in air services agreements, while controlling for other determinants. The results show up to 40% increase in departure frequency in routes that experienced some type of liberalization compared to those governed by restrictive bilateral air service agreements. Furthermore, there is a relatively larger increase in departure frequency in routes which experienced partial liberalization compared to fully liberalized ones. This can be explained by the diminishing marginal effect of progressive liberalization on departure frequency. While the effect of liberalization is substantial in improving service quality, there is no evidence of its fare reducing effect.

  • 10.
    Abate, Megersa
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Economic effects of air transport market liberalization in Africa2014Rapport (Annet vitenskapelig)
    Abstract [en]

    Although the aviation industry is increasingly becoming important for Africa's economic development and integration, the ability of airlines to access foreign markets remains hindered by restrictive regulatory policies. Attempts have been made to fully liberalize the intra-African air transport market. Except for general assertions about the merits/demerits of liberalization, our empirical understanding of the welfare effects of such polices in Africa remains rudimentary. This study empirically measures the economic effects of air transport liberalization, mainly on two supply side variables: fare and service quality, measured as departure frequency. The results show up to 40 % increase in departure frequency in routes that experienced some type of liberalization compared to those governed by restrictive bilateral air service agreements. While the effect of liberalization is substantial in improving service quality, there is no evidence of its fare reducing effect.

  • 11.
    Abate, Megersa
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    De Jong, Gerard
    University of Leeds.
    The optimal shipment size and truck size choice: The allocation of trucks across hauls2014Inngår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 59, s. 262-277Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There has been a growing interest in understanding how firms allocate their trucks across hauls, and how this allocation changes under various economic environments. This study investigates how variations in route/haul, carrier and vehicle characteristics affect the optimal vehicle size choice and the associated choice of shipment size. We show that the two choices are derived from the same optimization problem. There can be a continuum of shipment sizes, but decision-makers in freight transport have to choose from a limited number of vehicle alternatives. Therefore, we use a discrete-continuous econometric model where shipment size is modeled as a continuous variable, and vehicle size/type choice as a discrete variable. The results indicate that when faced with higher demand, and during longer trips firms are more likely to use heavier vehicles and ship in larger quantities which suggest that firms are realizing economies of scale and economies of distance. The study also discusses the effect of vehicle operating cost on the vehicle selection process and its policy implications.

  • 12.
    Abate, Megersa
    et al.
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Vierth, Inge
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    de Jong, Gerard
    University of Leeds.
    Joint econometric models of freight transport chain and shipment size choice2014Rapport (Annet vitenskapelig)
    Abstract [en]

    In freight transportation, decisions regarding the choice of transport mode (or chains of modes) and shipment size are closely linked. Building on this basic insight, in this paper we estimate and review various joint econometric models using the Swedish National Commodity Flow surveys. Robust parameter estimates from this exercise will be used to update the current deterministic Swedish national freight model system (the SAMGODS model) to a stochastic one.

  • 13.
    Abate, Megersa
    et al.
    World Bank.
    Vierth, Inge
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Karlsson, Rune
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Trafikanalys och logistik, TAL.
    de Jong, Gerard
    University of Leeds.
    Baak, Jaap
    dSignificance.
    A disaggregate stochastic freight transport model for Sweden2018Inngår i: Transportation, ISSN 0049-4488, E-ISSN 1572-9435, s. 1-26Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents estimation results for models of transport chain and shipment size choice, as well as an implementation of the estimated disaggregate models (for two commodity groups), in the context of the national freight transport model for Sweden. The new model is a disaggregate and stochastic (logit) model, whereas the existing Swedish national model is deterministic. One advantage of the new approach is that it bases the underlying behavior of shippers on a stronger empirical foundation (that is micro-data from the Swedish Commodity Flow Survey, CFS). Another advantage is that it overcomes a well-known disadvantage of deterministic models that lead to implausibly large responses to changes in scenario or policy variables. Although estimation and implementation of aggregate stochastic models were done before, in the context of a national freight transport forecasting model, we think this is the first implementation of disaggregate freight transport chain and shipment size models estimated on choice data for individual shipments, certainly in Europe. We carried out a number of model runs with both versions of the implemented model to compare elasticities and found that transport cost and time elasticities for tonne-km are smaller (in absolute values) in the disaggregate stochastic model than in their deterministic counterparts.

  • 14.
    Abbas, Khaled A
    Egyptian National Institute of Transport.
    Environmentally sustainable transport strategies: the way forward in metropolitan cities2001Inngår i: Proceedings of the conference Traffic Safety on Three Continents: International conference in Moscow, Russia, 19-21 September, 2001 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, Vol. 18A:3, s. 12-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper is concerned with one of the three requirements of a sustainable transport system, namely the environmental dimension. It starts by presenting components and interactions of the transport and traffic systems using causal diagrams. Generic traffic problems are identified and their causes categorized. A classification of demand and supply-based policies and measures that can be used in designing environmentally sustainable transport strategies is depicted. Such strategies are targeted towards minimizing the generic traffic problems encountered in metropolitan cities, i.e., traffic congestion, accidents, environmental degradation and energy inefficiencies. In this paper, Travel Demand and Land Use Management are considered as two of the basic pillars for designing environmentally sustainable transport strategies. Criteria for comparing demand versus supply-based policies are suggested. These are applied to assess the benefits and limitations of each policy, hence assisting decision makers in the prioritization and choice of such policies.

  • 15.
    Abbas, Khaled A
    et al.
    Egyptian National Institute of Transport.
    Al-Hosseiny, Ahmed T
    Egyptian National Institute of Transport.
    A generic approach for in depth statistical investigation of accident characteristics and causes2001Inngår i: Proceedings of the conference Traffic Safety on Three Continents: International conference in Moscow, Russia, 19-21 September, 2001 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, Vol. 18A:3, s. 13-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The main aim of this research is to develop a generic approach for the utilization of statistical methods to conduct depth investigation of road accident characteristics and causes. This approach is applied in an effort to analyse the 1998 accident database for the main rural roads in Egypt. This database is composed of traffic accident data collected for 14 road sections representing nine major roads of the Egyptian rural road network. The proposed approach is composed of two main stages of analysis. Within each stage, several analytical steps are conducted. The first stage is mainly concerned with developing cluster bar charts, where different characteristics and causes of accidents are portrayed in relation to variations in the three main accident contributing factors, namely types of roads, vehicles and drivers. The second stage is concerned with conducting in-depth statistical analysis of the collected accident data. Within this stage, four levels of statistical investigations were conducted. These are meant to examine a number of issues.

  • 16. Abdel-Aty, M A
    et al.
    Radwan, A E
    Developing crash predictive models for a principal arterial2000Rapport (Annet (populærvitenskap, debatt, mm))
  • 17. Abdel-Aty, MA
    et al.
    As-Saidi, AH
    Using GIS to locate the high risk driver population2000Rapport (Annet (populærvitenskap, debatt, mm))
  • 18.
    Abenoza, Roberto F.
    et al.
    KTH.
    Liu, Chengxi
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Trafikanalys och logistik, TAL.
    Cats, Oded
    KTH.
    Susilo, Yusak O.
    KTH.
    What is the role of weather, built-environment and accessibility geographical characteristics in influencing travelers’ experience?2019Inngår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 122, s. 34-50Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We examine the effect of weather, accessibility and built-environment characteristics on overall travel experience as well as the experience with the latest trips. These are factors that are often disregarded in the travel satisfaction literature even though they are believed to largely influence the first mile of the door-to-door trip. This study fills a research gap in investigating all these factors by using, amongst other, a relatively large travel satisfaction survey from years 2009 to 2015 and by focusing on urban and peri-urban geographical contexts, the city and county of Stockholm (Sweden), respectively. The ordered logit model results show that county dwellers living close to a metro station and in well linked-to-all areas report higher overall travel satisfaction evaluations. In addition, precipitation and ground covered with snow have a negative influence on travel satisfaction. Our findings indicate that built-environment characteristics exert a rather weak influence on the travel experience, especially in the peri-urban context. However, some aspects such as living in areas with medium densities, low income and with high safety perceptions around public transport stations are associated with higher satisfaction levels. In turn, areas with single land uses are found to have lower travel satisfactions. These results are important for public transport planners and designers in devising measures to prevent and mitigate the negative outcome of some weather conditions and to conceive better designed transit oriented developments.

  • 19.
    Abou-Senna, Hatem
    et al.
    University of Central Florida, Orlando.
    Radwan, Essam
    University of Central Florida, Orlando.
    Mohamed, Ayman
    University of Central Florida, Orlando.
    A methodology to quantify pedestrian crash rates against statewide averages for roadways and intersections2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To date there are no clear or uniform standards for a method to measure pedestrian crash rates and compare it against a statewide average. In this paper, a novel methodology to measure pedestrian crash rates along roadways and intersections were quantified. The main objective is to identify critical pedestrian crash locations that are operating above its corresponding statewide average.  It was crucial to address the pedestrian-vehicular conflict as the State of Florida currently tops the list in the “Dangerous by Design” report as having the highest four pedestrian incident locations in the Country. The main challenge was to identify a practical and correct exposure measure. In most cases, the exposure measure is either unavailable or can be obtained at a greater cost. The methods and procedures explained in this paper are considered detailed, practical and provide a broad depiction of the main factors that directly contribute to pedestrian crashes. The main parameters used in calculating pedestrian crash rates along roadways included functional classification, number of lanes, area type, AADT and the total length of the roadway category. Conversely, main parameters for computing pedestrian crash rates for intersections included daily pedestrian volumes, distance crossed and the AADT in addition to the number of pedestrian crashes either along the studied roadways or intersections. The pilot studies conducted for the roadways and intersections revealed several critical safety locations within District 5 when compared to the developed statewide average rates which required further investigation to identify main causes and emphasize mitigation improvements.

  • 20.
    Abrahamsson, Anna
    Statens väg- och transportforskningsinstitut.
    Hastigmätares felvisning1991Rapport (Annet vitenskapelig)
  • 21.
    Abrahamsson, Anna
    Statens väg- och transportforskningsinstitut.
    Metod för skattning av åtgärdseffekten vid saltning av vägar1989Rapport (Annet vitenskapelig)
  • 22.
    Abrahamsson, Anna
    et al.
    Statens väg- och transportforskningsinstitut.
    Junghard, Ola
    Statens väg- och transportforskningsinstitut.
    Reducerat faktorförsök med foldover för VTIs trafiksimuleringsmodell1992Rapport (Annet vitenskapelig)
  • 23.
    Abrahamsson, Anna
    et al.
    Statens väg- och transportforskningsinstitut.
    Ohlsson, Kjell
    Statens väg- och transportforskningsinstitut.
    Sjölinder, Kent
    Statens väg- och transportforskningsinstitut.
    Litteratursökning gällande olycksprediktionsmodeller och riskindex för plankorsningar mellan väg och järnväg1991Rapport (Annet vitenskapelig)
  • 24. Abrahamsson, Mats
    Ett centrallager i Europa i stället för femtio - lösningen på industrins logistikhandikapp1993Rapport (Annet (populærvitenskap, debatt, mm))
  • 25. Abrahamsson, Mats
    Forskares erfarenheter av artikelförfattande och publicering1994Rapport (Annet (populærvitenskap, debatt, mm))
  • 26.
    Abtahi, Farhad
    et al.
    Kungliga Tekniska Högskolan.
    Anund, Anna
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafikanttillstånd, TIL.
    Fors, Carina
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafikanttillstånd, TIL.
    Seoane, Fernando
    Kungliga Tekniska Högskolan.
    Lindecrantz, Kaj
    Kungliga Tekniska Högskolan.
    Association of drivers’ sleepiness with heart rate variability: A pilot study with drivers on real roads2018Inngår i: IFMBE Proceedings, Springer Verlag , 2018, Vol. 65, s. 149-152Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Vehicle crashes lead to huge economic and social consequences, and one non-negligible cause of accident is driver sleepiness. Driver sleepiness analysis based on the monitoring of vehicle acceleration, steering and deviation from the road or physiological and behavioral monitoring of the driver, e.g., monitoring of yawning, head pose, eye blinks and eye closures, electroencephalogram, electrooculogram, electromyogram and electrocardiogram (ECG), have been used as a part of sleepiness alert systems.

    Heart rate variability (HRV) is a potential method for monitoring of driver sleepiness. Despite previous positive reports from the use of HRV for sleepiness detection, results are often inconsistent between studies. In this work, we have re-evaluated the feasibility of using HRV for detecting drivers’ sleepiness during real road driving. A database consists of ECG measurements from 10 drivers, driving during morning, afternoon and night sessions on real road were used. Drivers have reported their average sleepiness level by using the Karolinska sleepiness scale once every five minutes. Statistical analysis was performed to evaluate the potential of HRV indexes to distinguish between alert, first signs of sleepiness and severe sleepiness states. The results suggest that individual subjects show different reactions to sleepiness, which produces an individual change in HRV indicators. The results motivate future work for more personalized approaches in sleepiness detection.

  • 27.
    Achit, Hamza
    et al.
    Université Paris-Est, IFSTTAR.
    Carnis, Laurent
    Université Paris-Est, IFSTTAR.
    Physical Impairment and Medical Care Spending by Road Accident Victims2013Inngår i: Proceedings of the 16th International Conference Road Safety on Four Continents: Beijing, China. 15-17 May 2013, Linköping: Statens väg- och transportforskningsinstitut, 2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    In addition to the immediate physical injuries they suffer, road accident victims may also be subject to ongoing deterioration of their state of health in terms of permanent physical and mental problems, disabilities, etc. These various health shocks entail recourse to care and treatment, the upshot being increases in health expenses. In France little is known about the financial impact of accidents on victims. This paper uses data from a sample of 777 individuals suffering from road accident-induced physical impairment. Information about these individuals includes details of their personal and socioprofessional characteristics, together with data provided by their health insurance offices regarding their use of treatment and their medical expenses. The analysis of these data reveals that the costs incurred by road accident victims are significantly associated with such factors as age, seriousness of impairment, and marital status. Interaction effects are also noted between these explanatory factors: for example, the effect of the seriousness of impairment on the costs involved differs according to the age of the victim.

  • 28.
    Achwan, Nawawi
    et al.
    Statens väg- och transportforskningsinstitut.
    Lanalywati,
    Statens väg- och transportforskningsinstitut.
    Application and development of road safety audit in Indonesia2001Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    The high rate of road accidents in Indonesia have become a national problem,

    which need serious handling. One of the causes, beside the human and vehicle

    factor, is the road and environmental factor. Based on international

    research, the contribution of road and environmental factors is calculated to

    24 %. This in turns stresses the importance of a strategy, which in the end

    lead to the improvement of road safety conditions through application of a

    road safety concept. The author strongly argues in favour of Road Safety

    Audits. A safety audit process could be applied at all stages - in the

    feasibility study before the road is constructed or rehabilitated, during all

    of the design phases and after the road have been in operation. Furthermore,

    this paper introduces the concept of road safety audit with an existing by

    pass road in Cirebon as an example.

  • 29.
    Adell, Emeli
    et al.
    Trivector Traffic.
    Nilsson, Annika
    Trivector Traffic.
    Kircher, Katja
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Samspel människa, fordon, transportsystem, MFT.
    Cyclists' use of mobile IT in Sweden: usage and self-reported behavioural compensation2014Inngår i: 3rd International Cycling Safety Conference (ICSC2014), 18-19 November, Gothenburg, Sweden: proceedings, Gothenburg, Sweden, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The increasing use of mobile phones while cycling has raised safety concerns. In this paper two studies of mobile phone use by cyclists are presented.

    The first study was designed to characterize mobile phone use by cyclists in Sweden, while the second studied how mobile phone use affected cyclist behaviour and compensation strategies. Mobile phone use was observed in about 20 percent of all urban bicycle trips. The usage varied with cyclist age with the highest usage among young cyclists. Of those using phones, 90% of the cyclists observed used head-phones.

    In parallel, standardized, interviews 15% of cyclists under 15 years old stated that they always used mobile phones while cycling. Listening to music in headphones was the most fre-quent self-reported activity. To converse using hand-held phones was also rather common, and was the only mobile phone usage reported by women above 50 years old.

    In the second study twenty-two young cyclists (age 16-25 years) completed a route in real traffic five times while listening to music, receiving and making calls, receiving and sending text messages, searching for information on the internet and while cycling normally without using the phone. The route and the types of tasks were controlled, but the cyclists could choose rather freely when, where and how to carry out the tasks. When the cyclist returned to the starting point, a short interview was conducted. During the interviews cyclists reported their experiences and the compensation strategies they used while cycling.

  • 30.
    Adell, Emeli
    et al.
    Trivector Sweden.
    Nilsson, Lena
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF.
    Várhelyi, András
    Lund University.
    How Is Acceptance Measured?: Overview of Measurement Issues, Methods and Tools2014Inngår i: Driver Acceptance of New Technology: Theory, Measurement and Optimisation / [ed] Michael A. Regan, Tim Horberry and Alan Stevens, Farnham, Surrey, England: Ashgate, 2014, s. 74-88Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    This chapter describes how acceptance has been measured and identifies various measurement categories. The relationship between these measurement methods and the different definitions of acceptance appearing in the literature is described and the lack of correspondence between definition and measurement is highlighted. The chapter illustrates the different outcomes of acceptance measurements depending on choice of assessment method and gives some guidance that could be used depending on the purpose of the assessment.

  • 31.
    Adell, Emeli
    et al.
    Trivector Sweden.
    Várhelyi, András
    Lund University.
    Nilsson, Lena
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF.
    Modelling Acceptance of Driver Assistance Systems: Application of the Unified Theory of Acceptance and Use of Technology2014Inngår i: Driver Acceptance of new technology: Theory, Measurement and Optimisation / [ed] Michael A. Regan, Tim Horberry and Alan Stevens, Farnham, Surrey, England: Ashgate, 2014, s. 23-34Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    This chapter provides a brief overview of acceptance models used within the area of information technology.  One particular model, the Unified Theory of Acceptance and Use of Technology (UTAUT), is then discussed, and a study is reported in which the model was used to assess driver acceptance of a particular driver assistance system. The key findings of that study are reported, and suggestions are made for refining UTAUT to make it more suitable for assessing acceptance of driver assistance systems.

     

  • 32.
    Adell, Emeli
    et al.
    Trivector Sweden.
    Várhelyi, András
    Lunds Universitet.
    Nilsson, Lena
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF.
    The Definition of Acceptance and Acceptability2014Inngår i: Driver Acceptance of New Technology: Theory, Measurement and Optimisation / [ed] Michael A. Regan, Tim Horberry and Alan Stevens, Farnham, Surrey, England: Ashgate, 2014, s. 11-21Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Despite the recognised importance of the concept of acceptance, how and why new technologies are actually accepted by drivers is not well understood. While many studies claim to have measured acceptance, few have explicitly defined what it is. This chapter points out the importance of defining acceptance and categorises definitions that have been used according to their “essence”. Distinctions between different types of acceptance as well as between acceptance and acceptability are also described. A proposal for a common definition of acceptance is then presented and discussed.

  • 33. Adesiyun, Adewole
    et al.
    Bezuglyi, Artem
    Bidnenko, Natalya
    Laszlo, Gaspar
    Golovko, Sergyi
    Kraszewski, Cezary
    Krayushkina, Kateryna
    Kushnir, Olexander
    Kuttah, Dina K
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Väg- och banteknik, VBA.
    Niska, Anna
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Sörensen, Gunilla
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafiksäkerhet, samhälle och trafikant, TST.
    Szpikowski, Miroslaw
    Andrezj, Urbanik
    Voloshyna, Iryna
    Vozniuk, Andrii
    Vyrozhemsky, Valeriy
    Short-term Research Visits2014Rapport (Annet (populærvitenskap, debatt, mm))
  • 34. Admasie, D
    et al.
    Stenberg, L
    Statens väg- och transportforskningsinstitut.
    Equipment for frost heave tests: Friction between plastic and soil1982Rapport (Annet vitenskapelig)
  • 35. Adolehoume, Amakoe
    et al.
    Muhlrad, Nicole
    Road safety policies in seven West African countries2001Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    At the end of 1999, UEMOA, the Economic and Monetary Union for West Africa,

    launched a study of the road safety situation and management processes in

    seven of the eight countries of the Union (Benin, Burkina Faso, Cite

    d'Ivoire, Mali, Niger, Senegal, Togo), in view of formulating Communal Road

    Safety Policies at the regional level. A team of African and European

    "experts" was formed to establish a diagnosis on each country as well as a

    global assessment of the situation in the region, and to draw proposals for

    action. The final report was published in March 2000 and is now being

    evaluated by UEMOA and integrated into a wider proposal for transport

    policies, for presentation at a round table of donors. The present paper does

    not provide a complete summary of the outcome of the study, but presents a

    selection of some difficult problems encountered in the countries

    investigated and directions for possible solutions as seen by the researchers

    and consultants that took part in the study. Comprehensive proposals and

    guidelines for Communal Road Safety Policies are not included as they have

    not officially been accepted by UEMOA yet, but the original report can be

    requested from this organisation in Ouagadougou. A brief outline of the

    approach and methodology used is described. More complete methodological

    guidelines, developed from the experience gathered through the UEMOA study as

    well as previous ones carried out by Inrets (the French National Institute

    for Transport and Safety Research) will be published at a later stage.

  • 36. Adolph, T.
    et al.
    Schwedhelm, H.
    Lazaro, I.
    Versmissen, T.
    Edwards, M.
    Thomson, Robert
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafiksäkerhet, samhälle och trafikant, TST.
    Johannsen, H.
    Development of compatibility assessments for full-width and offset frontal impact test procedures in FIMCAR2014Inngår i: International Journal of Crashworthiness, ISSN 1358-8265, E-ISSN 1754-2111, Vol. 19, nr 4, s. 414-430Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The goal of the project FIMCAR (Frontal Impact and Compatibility Assessment Research) was to define an integrated set of test procedures and associated metrics to assess a vehicle's frontal impact protection, which includes self-And partner-protection. For the development of the set, two different full-width tests (full-width deformable barrier [FWDB] test, full-width rigid barrier test) and three different offset tests (offset deformable barrier [ODB] test, progressive deformable barrier [PDB] test, moveable deformable barrier with the PDB barrier face [MPDB] test) have been investigated. Different compatibility assessment procedures were analysed and metrics for assessing structural interaction (structural alignment, vertical and horizontal load spreading) as well as several promising metrics for the PDB/MPDB barrier were developed.The final assessment approach consists of a combination of the most suitable full-width and offset tests. For the full-width test (FWDB), a metric was developed to address structural alignment based on load cell wall information in the first 40 ms of the test. For the offset test (ODB), the existing ECE R94 was chosen. Within the paper, an overview of the final assessment approach for the frontal impact test procedures and their development is given.

  • 37.
    Adolph, Thorsten
    et al.
    Federal Highway Research Institute.
    Eggers, Andre
    Federal Highway Research Institute.
    Thomson, Robert William
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafiksäkerhet, samhälle och trafikant, TST.
    Mizuno, Koji
    Nagoya University.
    Comparison of the dummy response in two different restraint system crash tests2014Inngår i: 2014 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury, 2014, s. 545-561Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the European Project FIMCAR, a proposal for a frontal impact test configuration was developed which included an additional full width deformable barrier (FWDB) test. Motivation for the deformable element was partly to measure structural forces as well as to produce a severe crash pulse different from that in the offset test. The objective of this study was to analyse the safety performance of vehicles:

    • in the full width rigid barrier test (FWRB) and
    • in the full width deformable barrier test (FWDB)

    In total, 12 vehicles were crashed in both configurations. Comparison of these tests to real world accident data was used to identify the crash barrier most representative of real world crashes. For all vehicles, the airbag visible times were later in the FWDB configuration. This was attributed to the attenuation of the initial acceleration peak, observed in FWRB tests, by the addition of the deformable element. These findings were in alignment with airbag triggering times seen in real world crash data. Also, the dummy loadings were slightly worse in FWDB compared to FWRB tests, which is possibly linked to the airbag firing and a more realistic loading of the vehicle crash structures in the FWDB configuration. Evaluations of the lower extremities have shown a general increasing of the tibia index with the crash pulse severity.

  • 38. Agebjörn, Anika
    Transportforskningen som populärvetenskap1991Rapport (Annet (populærvitenskap, debatt, mm))
  • 39. Agustsson, Larus
    Automatic speed control: The Danish pilot project2001Inngår i: Proceedings of the conference Traffic Safety on Three Continents: International conference in Moscow, Russia, 19-21 September, 2001 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, Vol. 18A:2, s. 7-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The goal of the new Danish Road Safety Action Plan is to reduce the number of traffic accident fatalities and serious casualties by 40% from 1998 to the year 2012. This plan is ambitiously titled "Each Accident is One Too Many". The four main areas of the accident plan are accidents caused by speeding, accidents caused by intoxicated drivers, accidents with bicyclists, and accidents at intersections. This paper deals with the first type of accident in the plan - accidents caused by speeding. Specifically, the paper describes the automatic speed control pilot project in Denmark.

  • 40. Agustsson, Larus
    Danish experiences with speed zones/variable speed limits2001Inngår i: Proceedings of the conference Traffic Safety on Three Continents: International conference in Moscow, Russia, 19-21 September, 2001 / [ed] Asp, Kenneth, Linköping: Statens väg- och transportforskningsinstitut, 2001, Vol. 18A:3, s. 12-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The first Danish Road Safety Action plan in 1989 reduced the number of fatalities and casualties by 30% by the year 2000. The goal of the new Danish Road Safety Action Plan is to reduce the number of fatalities and serious casualties by 40% from 1998 to the year 2012. One of the actions that will be used to actuate this plan is the implementation of speed management and speed zones. This paper discusses the Danish experience with speed zones and variable speed limits

  • 41.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S. Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Analysis of discrete multi-unit, common value auctions: a study of three sealed-bid mechanisms2012Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    This paper proposes a discrete bidding model for both quantities and pricing. It has a two-unit demand environment where subjects bid for contracts with an unknown redemption value, common to all bidders. Prior to bidding, the bidders receive private signals of information on the (common) value. The value and the signals are drawn from a known discrete affiliated joint distribution. The relevant task for the paper is to compare the equilibrium strategies and the seller’s revenue of three auction formats. We find that, of the three auctionformats below with two players, the discriminatory auction always gives the largest revenue to the seller; both the uniform and the Vickrey auction have zero revenue equilibrium strategies that put them further down in the revenue ranking. In equilibrium, bidders bid the same amount on both items in the discriminatory auction; a phenomenon not noted in either of the other auction formats.

  • 42.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Energimätning på tåg för rundvirkestransporter på sträckan Mora–Borlänge–Gävle2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    I det tredje delprojektet av ELVIS-demonstrationsprojektet för längre och tyngre godståg är syftet att mäta energianvändningen som ett tyngre tågset ger upphov till. Med tyngre avses här en ökad totalvikt genom fler vagnar, både fullastade och olastade, än vad som normalt körs på sträckan. Antagandet är att det med tyngre tåg finns möjlighet att göra (gods)transporter mer energieffektiva. Målsättningen är att framför allt testa hypotesen: · Att energianvändningen per tonkilometer kan reduceras genom att använda tyngre tåg. Rapporten belyser svårigheterna med att använda befintlig data för utvärdering av vad som driver energianvändningen på tåg. Datat i har inte varit kvalitetssäkrad för ändamålen i denna studie, vilket har orsakat en hel del fel och tillförlitligheten på vissa resultat är lägre än de skulle behöva vara. En slutsats från projektet att det skulle behövas en genomgång av databaserna hos Trafikverket om energianvändning ska studeras närmare, i alla fall om Trafikverkets utrustning för energimätning ska användas. Alternativt bör extern utrustning monteras på loken för att på så vis generera mer ändamålsenlig data, det senare var dock omöjligt då lokägaren inte godkände det. En annan slutsats är att körstilen spelar roll, det skiljer upp till 20 procent använd nettoenergi mellan förarna. Givet alla felkällor har ändå en regressionsanalys gjorts för att analysera hur energianvändningen för ett godståg kan bero på bruttovikten på tåget samt antal stopp tåget gör. Resultaten indikerar att det är skillnader på energianvändning för olika bruttovikter på tåget, men då det är oklart hur resultaten ska tolkas så krävs det mera mätningar för att kunna säga något bestämt. Detsamma gäller för hur antalet stopp påverkar användningen av energi, i en mätning fick vi ingen påverkan på energianvändningen av antal stopp medan vi fick det i en annan.

  • 43.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Intermodala transporter: definition, aktörer och omfattning2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Intermodala transporter och kombinerade transporter används ofta synonymt idag. Begreppet kombinerade transporter har dock funnits mycket längre och avsåg då transporter där järnvägen och lastbilar kombinerades. Numer räknas en kombinerad transport som att lasten antingen går på järnväg, inre vattenvägar eller till havs och med lastbil, eller mellan två trafikslag där inte lastbil är inkluderat.

    En intermodal transport föregås av ett transportbeslut och för många typer av gods är inte en intermodal transport rimlig, till exempel för virkes- och bulktransporter, medan det för andra varor, såsom detaljhandels- och livsmedelsvaror, finns en valmöjlighet hur godset ska transporteras. Det är då som aktivt beslut kan tas för en intermodal transport, givet att den som äger transportbeslutet känner till transportsättet i fråga. Transportbeslutet är också styrt av tåglägen, finns inte kapacitet på spåren kan inte transporter göras med järnväg. Detta kan potentiellt innebära att vissa (tåg)affärer/transporter inte blir av och godset går på vägen istället.

  • 44.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Kostnader för störningar i infrastrukturen: metodik och fallstudier på väg och järnväg2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Studien i detta notat belyser metodiken som kan användas vid beräkningar av samhällets kostnader vid störningar i samhällets infrastruktur, framför allt väg- och järnvägstrafik. Ur ett samhällsekonomiskt perspektiv innebär störningar i infrastrukturen kostnader till följd av förseningar, utebliven produktion och kostnader för omledningar med mera. Det är av vikt att beskriva vilken belastning i form av förlorade eller förbrukade resurser som dessa störningar av olika slag innebär för samhället. Utgångspunkten för beräkningen av kostnaderna har varit genom den samhällsekonomiska kalkylen, med kalkylvärden från ASEK (Arbetsgruppen för samhällsekonomisk analysmetod inom transportsektorn); såsom åktidsvärden, förseningstidsvärden samt trängseltidsvärden. Den värdering av tid som görs i transportsektorns samhällsekonomiska kalkyler avser det marginella värdet av en inbesparad timme restid, väntetid eller bytestid för personresor och transporttid för gods.

  • 45.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi, TEK.
    Luftfartens samhällsekonomiska marginalkostnader: delstudie inom SAMKOST2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    Den här rapporten är en litteraturstudie av luftfartens samhällsekonomiska marginalkostnader. Den utgör ett delprojekt till VTI:s regeringsuppdrag om att uppdatera kunskapen kring trafikens samhällsekonomiska kostnader (SAMKOST). I rapporten diskuteras vilka effekter som är externa för luftfarten, och vilka som redan är internaliserade. Det är inte helt självklart vilka effekter som bör beaktas som relevanta marginalkostnader för luftfarten. Till exempel kan både trängsel och olyckor ses som internaliserade då de redan är omhändertagna av flygledartjänsten, ett verktyg som alla flygplan måste använda sig av i svenskt luftrum enligt lag. Detsamma gäller infrastrukturen. Den stora externa effekten är flygets miljöpåverkan. Här skiljs på tre olika kategorier; bullerpåverkan, luftkvalitépåverkan och klimatpåverkan.

  • 46.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S. Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Multi-unit common value auctions: a laboratory experiment with three sealed-bid mechanisms2012Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    This study addresses a discrete common value environment with independent (one-dimensional) private signals, where the seller offers two identical units and the buyers have (flat) demand for both. Each session is conducted with2, 3 or 4 buyers. Three auction formats are used: the discriminatory, uniformand Vickrey auctions which are all subjected to a variation in the number of bidders and to repeating bid rounds on each subject. The main findings are that there are no significant differences between the uniform and the discriminatory auction in collecting revenue, while the Vickrey auction comes out as inferior. More bidders in the auction result in a greater revenue and level out the performance across the mechanisms. Demand reduction is visible in the experiment, but it is not as prominent as anticipated. Moreover, subjects come closer to equilibrium play over time. Finally, the winner’s curse is less severe than what is reported for inexperienced bidders in other studies.

  • 47.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S. Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Multi-unit common value auctions: an experimental comparison between the static and the dynamic uniform auction2012Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    It is still an open question whether the dynamic or the static format should be used in multi-unit settings, in a uniform price auction. The present study conducts an economic experiment in a common value environment, where it is found that it is more a question of whether the auctioneer wants to facilitate price discovery, and thereby lessen the otherwise pervasive overbidding, or if only the revenue is important. The experiment in the present paper provides evidence that the static format gives a significantly greater revenue than the dynamic auction, in both small and large group sizes. But a higher revenue comes at a cost; half of the auctions in the static format yield negative profits to the bidders, the winner’s curse is more severely widespread in the static auction, and only a minority of the bidders use the equilibrium bidding strategy.

  • 48.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S. Örebro universitet, Handelshögskolan vid Örebro Universitet.
    Multi-unit common value auctions: theory and experiments2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Research on auctions that involve more than one identical item for sale was,almost non-existing in the 90’s, but has since then been getting increasing attention. External incentives for this research have come from the US spectrum, sales, the European 3G mobile-phone auctions,  and Internet auctions. The policy relevance and the huge amount of money involved in many of them have helped the theory and experimental research advance. But in auctions where values are equal across bidders, common value auctions, that is, when the value depends on some outside parameter, equal to all bidders, the research is still embryonic.

    This thesis contributes to the topic with three studies. The first uses a Bayesian game to model a simple multi-unit common value auction, the task being to compare equilibrium strategies and the seller’s revenue from three auction formats; the discriminatory, the uniform and the Vickrey auction. The second study conducts an economic laboratory experiment on basis of the first study. The third study comprises an experiment on the multi-unit common value uniform auction and compares the dynamic and the static environments of this format.

    The most salient result in both experiments is that subjects overbid. They are victims of the winner’s curse and bid above the expected value, thus earning a negative profit. There is some learning, but most bidders continue to earn a negative profit also in later rounds. The competitive effect when participating in an auction seems to be stronger than the rationality concerns. In the first experiment, subjects in the Vickrey auction do somewhat better in small groups than subjects in the other auction types and, in the second experiment, subjects in the dynamic auction format perform much better than subjects in the static auction format; but still, they overbid.

    Due to this overbidding, the theoretical (but not the behavioral) prediction that the dynamic auction should render more revenue than the static fails inthe second experiment. Nonetheless, the higher revenue of the static auction comes at a cost; half of the auctions yield negative profits to the bidders, and the winner’s curse is more severely widespread in this format. Besides, only a minority of the bidders use the equilibrium bidding strategy.The bottom line is that the choice between the open and sealed-bid formats may be more important than the choice of price mechanism, especially in common value settings.

    Delarbeid
    1. Analysis of discrete multi-unit, common value auctions: a study of three sealed-bid mechanisms
    Åpne denne publikasjonen i ny fane eller vindu >>Analysis of discrete multi-unit, common value auctions: a study of three sealed-bid mechanisms
    2012 (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    This paper proposes a discrete bidding model for both quantities and pricing. It has a two-unit demand environment where subjects bid for contracts with an unknown redemption value, common to all bidders. Prior to bidding, the bidders receive private signals of information on the (common) value. The value and the signals are drawn from a known discrete affiliated joint distribution. The relevant task for the paper is to compare the equilibrium strategies and the seller’s revenue of three auction formats. We find that, of the three auctionformats below with two players, the discriminatory auction always gives the largest revenue to the seller; both the uniform and the Vickrey auction have zero revenue equilibrium strategies that put them further down in the revenue ranking. In equilibrium, bidders bid the same amount on both items in the discriminatory auction; a phenomenon not noted in either of the other auction formats.

    Publisher
    s. 27
    Emneord
    Economics
    HSV kategori
    Forskningsprogram
    SAB, Qa Economics and finance
    Identifikatorer
    urn:nbn:se:vti:diva-5313 (URN)
    Tilgjengelig fra: 2013-12-03 Laget: 2013-12-03 Sist oppdatert: 2016-02-04bibliografisk kontrollert
    2. Multi-unit common value auctions: a laboratory experiment with three sealed-bid mechanisms
    Åpne denne publikasjonen i ny fane eller vindu >>Multi-unit common value auctions: a laboratory experiment with three sealed-bid mechanisms
    2012 (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    This study addresses a discrete common value environment with independent (one-dimensional) private signals, where the seller offers two identical units and the buyers have (flat) demand for both. Each session is conducted with2, 3 or 4 buyers. Three auction formats are used: the discriminatory, uniformand Vickrey auctions which are all subjected to a variation in the number of bidders and to repeating bid rounds on each subject. The main findings are that there are no significant differences between the uniform and the discriminatory auction in collecting revenue, while the Vickrey auction comes out as inferior. More bidders in the auction result in a greater revenue and level out the performance across the mechanisms. Demand reduction is visible in the experiment, but it is not as prominent as anticipated. Moreover, subjects come closer to equilibrium play over time. Finally, the winner’s curse is less severe than what is reported for inexperienced bidders in other studies.

    Publisher
    s. 35
    Emneord
    Economics, Ekonomi
    HSV kategori
    Forskningsprogram
    SAB, Qa Economics and finance
    Identifikatorer
    urn:nbn:se:vti:diva-5314 (URN)
    Tilgjengelig fra: 2013-12-03 Laget: 2013-12-03 Sist oppdatert: 2014-06-10bibliografisk kontrollert
    3. Multi-unit common value auctions: an experimental comparison between the static and the dynamic uniform auction
    Åpne denne publikasjonen i ny fane eller vindu >>Multi-unit common value auctions: an experimental comparison between the static and the dynamic uniform auction
    2012 (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    It is still an open question whether the dynamic or the static format should be used in multi-unit settings, in a uniform price auction. The present study conducts an economic experiment in a common value environment, where it is found that it is more a question of whether the auctioneer wants to facilitate price discovery, and thereby lessen the otherwise pervasive overbidding, or if only the revenue is important. The experiment in the present paper provides evidence that the static format gives a significantly greater revenue than the dynamic auction, in both small and large group sizes. But a higher revenue comes at a cost; half of the auctions in the static format yield negative profits to the bidders, the winner’s curse is more severely widespread in the static auction, and only a minority of the bidders use the equilibrium bidding strategy.

    Publisher
    s. 35
    Emneord
    Economics, Ekonomi
    HSV kategori
    Forskningsprogram
    SAB, Qa Economics and finance
    Identifikatorer
    urn:nbn:se:vti:diva-5315 (URN)
    Tilgjengelig fra: 2013-12-03 Laget: 2013-12-03 Sist oppdatert: 2014-06-10bibliografisk kontrollert
  • 49.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Optimal taxation of intermediate goods in the presence of externalities: A survey towards the transport sector2004Rapport (Annet vitenskapelig)
    Abstract [sv]

    The paper surveys the literature on optimal taxation with emphasis on intermediate goods, or, more specific, freight (road) transport. There are two models frequently used, first, the one emanated from Diamond & Mirrlees' (1971) paper, where the production efficiency lemma made it clear that intermediate goods was not to be taxed. And, second, the Ramsey-Boiteux model where a cost-of-service regulation imposes a budget constraint for the regulated firm. In the latter model, in contrast to the first, freight transports (intermediate goods) are to be taxed in the Ramsey tradition, and thus trades the production efficiency lemma against a budget restriction. The paper also discusses welfare effects due to environmental tax reforms, with emphasis to what has become to known as the double dividend hypothesis. Finally, administrative costs in the context of optimal taxation is touched upon, a subject that is to a large degree repressed in optimal tax theory.

  • 50.
    Ahlberg, Joakim
    Statens väg- och transportforskningsinstitut, Samhälle, miljö och transporter, SAMT, Transportekonomi Stockholm, TEK-S.
    Optimal taxation of intermediate goods in the presence of externalities: A survey towards the transport sector2006Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    The paper surveys the literature on optimal taxation with emphasis on intermediate goods, or, more specific, freight (road) transport. There are two models frequently used, first, the one emanated from Diamond & Mirrlees' (1971) paper, where the production efficiency lemma made it clear that intermediate goods was not to be taxed. And, second, the Ramsey-Boiteux model where a cost-of-service regulation imposes a budget constraint for the regulated firm. In the latter model, in contrast to the first, freight transports (intermediate goods) are to be taxed in the Ramsey tradition, and thus trades the production efficiency lemma against a budget restriction. The paper also discusses welfare effects due to environmental tax reforms, with emphasis to what has become to known as the double dividend hypothesis. Finally, administrative costs in the context of optimal taxation is touched upon, a subject that is to a large degree repressed in optimal tax theory.

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