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1.
  • Nilsson, Jan-Eric, 1952-, et al. (författare)
  • Railway timetabling for the future? : A pilot study on a single track line
  • 2023
  • Ingår i: Journal of Rail Transport Planning & Management. - : Elsevier. - 2210-9706 .- 2210-9714. ; 27:September
  • Tidskriftsartikel (refereegranskat)abstract
    • No country uses optimisation methods to establish a value maximising allocation of operators’ demand for scarce railway infrastructure. Using the same input as was used in the year 2020 (T20), when the official timetable for one specific line in Sweden was developed by the infrastructure manager, this paper presents the outcome of the combined use of dual optimisation and rapid branching to produce a solution to an actual optimisation problem. These methods generate a timetable with the same number of trains as in T20 and some qualities that are better than those of the official timetable. The pilot study therefore confirms that it is worthwhile to further develop formal optimisation mechanisms towards larger-scale applications. Being able to handle conflicts-of-interest on a single-track line means that the problem on a double track line has fewer restrictions.
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2.
  • Nilsson, Jan-Eric, 1952-, et al. (författare)
  • Using a self-selection mechanism for tendering in the construction industry : a case study of railway renewal contracts
  • 2023
  • Rapport (refereegranskat)abstract
    • One of the consequences of the institutional separation of railway infrastructure from train operations in Europe is a misalignment of incentives in which the actions of one party may create costs for the other. To internalise otherwise external costs of track-works experienced by train operators and customers, it is essential to reform the way in which project contracts are tendered. This study suggests a self-selection mechanism for tendering rail infrastructure activities. Bidders may therefore submit bids based on the industry’s standard Unit Price Contract or a Fixed-Price Contract. The mechanism is designed to increase the possibility for a welfare maximising trade-off between construction and user costs. Using standard Benefit-Cost principles and parameter values, a case study where five switches are replaced provides substance to the discussion. The study provides a starting point for addressing risk in the construction industry and a blueprint for further development by professionals to fill in gaps and to test the approach under a controlled format before full-scale implementation. 
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3.
  • Odolinski, Kristofer, 1984-, et al. (författare)
  • Att följa upp och utvärdera järnvägsunderhåll : Delrapport inom projektet Metod för jämförelsestudier av järnvägsunderhåll
  • 2023
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Med start 2025 avser Trafikverket förändra formerna för upphandling av basunderhåll i tre geografiska områden. Förändringarna innebär att en större mängd planering och produktionsledning sker i Trafikverkets regi. Syftet är att utveckla den egna beställarförmågan och att stärka leverantörsmarknaden.VTI har fått Trafikverkets uppdrag att föreslå metoder för att kunna följa upp konsekvenserna av den förändrade organisationen. I rapporten redovisas uppdragets första del med fokus på konsekvenserna av ett förändrat ansvar för basunderhåll av Södra Malmbanan. Syftet med delstudien är att identifiera den information som krävs och de metoder som kommer att användas för att fördjupa förståelsen av hur den nya ansvarsfördelningen förändrar kostnader och förutsättningarna för trafik jämfört med dagens förfarande. Förutom att skapa goda förutsättningar att utvärdera de förändringar som genomförs kommer detta arbete också att kunna ge stöd för övergången till nya verksamhetsupplägg i de ytterligare två områden som står på tur att förändras, Ostkustbanan (2026) och Mälarbanan (2027). Information har inhämtats från personal inom Trafikverket och från aktörer på leverantörsmarknaden, samt via analyser av dokumentationen av underhållsverksamheten liksom en genomgång av relevant litteratur.De betydande förändringar av verksamheten som förestår kan få konsekvenser i flera avseenden. För att kunna följa upp och jämföra kostnader och andra utfall i hela landet krävs uppgifter från samtliga kontraktsområden med avseende på verksamhetens kostnader, omfattning (antal kilometer bana, installationer av växlar och konstbyggnader), trafik, väder etcetera. Tack vare att Trafikverket sedan länge byggt upp databaser som innehåller den aktuella informationen är en viktig del av det fortsatta arbetet att etablera ett smidigt tillvägagångssätt för att årligen kunna komplettera informationen och göra nya observationer av förändringar som kan ha inträffat. Ett antal frågeställningar föreslås som kan besvaras med stöd av en analys av det föreslagna materialet. Svaret på dessa frågor gör det möjligt att stärka förståelsen av den verksamhet som bedrivs och att ta fram kunskap som kan omsättas i praktiken.
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4.
  • Odolinski, Kristofer, 1984-, et al. (författare)
  • Damage or no damage from traffic : Re-examining marginal cost pricing for rail signalling maintenance
  • 2023
  • Ingår i: Transport Policy. - : Elsevier Ltd. - 0967-070X .- 1879-310X. ; 131, s. 13-21
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper re-examines the implementation of the short run marginal cost (SRMC) pricing principle with respect to rail infrastructure usage and empirically tests if there are rail infrastructure maintenance costs triggered by traffic but not caused by asset damage from traffic. This is important because current EU legislation stipulates that only costs related to infrastructure wear and tear from traffic are eligible for the direct cost-based element of track access charges. An econometric approach is applied to French panel data on signalling maintenance costs. The results show that the SRMC for infrastructure provision of these assets is not only related to asset damage costs caused by traffic, but can also be due to economic factors linked to increased line capacity utilisation: 1) higher cost per maintenance activity, and/or 2) increased preventative maintenance to curb delays. Our work offers an explanation as to why econometric and engineering approaches give different views of rail infrastructure cost variability and suggests that EU legislation on track access pricing may need to be revised. © 2022 The Author(s)
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5.
  • Ridderstedt, Ivan, et al. (författare)
  • Economies of scale versus the costs of bundling : Evidence from procurements of highway pavement replacement
  • 2023
  • Ingår i: Transportation Research Part A. - : Elsevier BV. - 0965-8564 .- 1879-2375. ; 173
  • Tidskriftsartikel (refereegranskat)abstract
    • Although most public procurements involve decisions concerning bundling, only a limited body of empirical research guides policy on this matter. In this paper, we examine the cost effects of bundling in the competitive tendering of highway pavement replacement with hot-mix asphalt. For this we use linear regression on data from a comprehensive sample of such contracts procured by the Swedish infrastructure manager (IM) during the 2012–2015 period. We find that bundling affects the procurer's cost in multiple and partly counteracting ways. Our results show that economies of scale are strong but diminishing and counteracted by the costs of bundling and bundling-related factors. Overall, the findings support the Swedish IM's current bundle design but also suggest that most of the contracts are still inefficiently small. While not perfectly generalizable to other markets, the findings provide some support for the increased promotion and use of the bundling of small-scale road rehabilitation projects in the USA. Two main implications of the results are that bundling policy should emphasize proximity and similarity rather than whether the work is small in scale and that the scope for efficient bundling should be accounted for when optimizing the timing of pavement replacement.
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6.
  • Ridderstedt, Ivan, 1990- (författare)
  • Improving the Efficiency of Public Procurement : Empirical evidence using micro-level contract data
  • 2023
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Among OECD countries, close to one-third of government expenditure is allocated using public procurement. This implies that the skill of public authorities in handling the procurement format has a significant impact on how much the public sector accomplish in relation to their goals and responsibilities. The aim of this thesis is to provide new insights into how public procurers can achieve more for the money by improving the design of their auctions and contracts. Specifically, the thesis examines how the efficiency can be influenced by the following three aspects: the method of bid evaluation (the award mechanism), whether items are procured separately or grouped into larger contracts, and variations among procurers in the activities and quantities they specify in a given case.The thesis includes four essays that analyze detailed contract information from Swedish procurements of road reinvestments and public bus services. For a comprehensive sample of the examined contracts, information has been collected from procurement documents and compiled into rich microdata sets. The use of microdata has enabled detailed reviews of how the procurements have been designed as well as statistical analysis of associations between the procurer’s choices and the outcome. While the essays primarily focus on results and implications regarding their respective research questions, the kappa provides a more general discussion about quantitative microanalysis in the field of procurement. This reflects a complementary aim of the thesis, which is to contribute to well-informed decisions regarding whether and how contracting authorities should facilitate analyses of this kind.Two of the essays investigate to what extent and how the Swedish national infrastructure manager Trafikverket can improve its efficiency in procurements of highway pavement replacement. Trafikverket spends approximately EUR 200 million on these works annually. Hence, if better procurement methods could lower the cost by 5% without reducing the quality, about EUR 10 million would be freed up annually for additional road maintenance or other uses. Both essays indicate that even greater efficiency gains can be achieved through improved dissemination of best practices. The results support Trafikverket's policy to bundle similar and adjacent road work but imply that the contracts are generally not large enough to fully benefit from the economies of scale. A conclusion is that it is motivated for Trafikverket to consider the scope for efficient bundling when deciding on the timing of these pavement replacement measures.The other two essays examine how the Swedish regional Public Transport Authorities (PTAs) have implemented the scoring rule award mechanism and its efficiency. This alternative to the lowest price and quality-only mechanisms is promoted within the EU procurement directive and is dominant in many countries. However, the literature on how well public agencies implement this policy is scarce and fragmented. One of the essays shows that scoring rules are common in Swedish procurements of public bus services, but also that there are significant differences between the PTAs in whether and how they have applied this award mechanism. Several implementations have unsound and likely unintended properties, in the light of economic theory. The findings suggest that best practices are not spread effectively between the organizations. The second essay on this theme exploits the property that one PTA alternated between lowest price and a performance focused variant of scoring rules and, equally important, could provide data on a relevant and reliable outcome measure. Based on 30 months of observations on monitored punctuality, performance is not found to be better in contracts awarded using scoring rules. The results suggest that the promotion of scoring rules is not accompanied with adequate guidance on when and how to implement it efficiently.The kappa highlights how microdata at the contract level enable research that considers both the ‘uniqueness’ of each procurement and random variation. In the analyses of road reinvestments, the detailed data allows us to consider several important characteristics of the contracts and the treated road segments. Similarly, the analysis of bus punctuality considers several aspects of the traffic assignment. In this way, quantitative microanalysis can provide reliable quantifications of how costs and quality are affected by both the procurer's actions, while considering the external conditions. Many of these associations are too complex to be reliably assessed by an individual civil servant, even if it is highly knowledgeable and experienced. However, the thesis emphasizes that even quantitative analysis can yield misleading results if the data material is not good enough, for example, if the sample is too small or relevant aspects are not captured.A central argument in the thesis is that the standardized and rigid procurement process creates particularly excellent conditions for collecting useful procurement data. However, the potential for this has largely remained untapped by the public agencies themselves. Instead, these data have primarily been compiled within individual research projects, where even the collection of tendering documents has been a notorious obstacle. In Sweden, Trafikverket's information management and cost control have repeatedly been criticized. However, Trafikverket is far from the ‘worst in class’ in these matters, and the criticism mainly reflects the agency's position as one of Sweden's largest procurers. An overall conclusion of the thesis is that public agencies in general should take a more active role in improving how procurement data are collected and managed. Of particular importance is the establishment of well-structured archiving processes for procurement documents, along with systems to track changes in both costs and content after a contract is awarded. For smaller authorities, it is reasonable that this development is coordinated or driven by a centralized function, whereas Trafikverket is well positioned to take a leading role in finding and disseminating best practices. Ultimately, the responsibility for instructing and overseeing improvements in this area lies with the governing bodies of the public agencies, given that the agencies do not set their own agendas.
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7.
  • Smith, Andrew S. J., et al. (författare)
  • Efficiency measurement in the tendering of road surface renewal contracts
  • 2023
  • Ingår i: Journal of Productivity Analysis. - : Springer Nature. - 0895-562X .- 1573-0441.
  • Tidskriftsartikel (refereegranskat)abstract
    • The problem of slow productivity growth in the road construction (and wider construction) industry is well known. The present paper suggests a means for efficiency analysis in one part of this industry, namely road surface renewal in Sweden, built upon the application of Stochastic Frontier Analysis (SFA) techniques. The paper is novel in that it focuses on project level rather than firm or contractor level performance and takes the perspective of the inefficiency that may result from the way the contracts are specified by the highway agency’s pavement engineers (client side). We compare 233 renewal contracts tendered over a four-year period via the estimation of a cost frontier, with controls for heterogeneity between projects. Our results produce first estimates that expose substantive differences in the relative efficiency performance of different engineers within the Swedish highways procurement organisation (Trafikverket); with indicative savings of around €40 m out of a total road renewals budget in Sweden of €200 m. We also find substantial economies of scale that could, in principle, point to further cost savings if road renewal projects can be packaged up as larger projects. These client-side savings represent potentially important sources of savings in addition to those that can be achieved through the pressure of competitive tendering on the supplier side. The paper therefore illustrates how disaggregate analysis of project level information can readily be used for revealing important information about how best to frame the procurement process and thus deliver productivity and unit cost improvements over time. 
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8.
  • Nilsson, Jan-Eric, 1952- (författare)
  • The Weak Spot of Infrastructure BCA : Cost Overruns in Seven Road and Railway Construction Projects
  • 2022
  • Ingår i: Journal of Benefit-Cost Analysis. - : Cambridge University Press. - 2194-5888 .- 2152-2812. ; 13:2, s. 224-246
  • Tidskriftsartikel (refereegranskat)abstract
    • This article describes the process from first proposals in the early 1990s to project completion many years later for seven large Swedish road and railway projects. The purpose is to find reasons for the massive cost overruns as well as explanations for why projects are brought to completion despite much higher costs than when the decision to build was made. Cost overruns are set in an institutional context to highlight the interplay among national, regional, and local policymakers. National investment programs are seen as promises by other parts of society, irrespective of whether project costs increase during the process toward procurement and implementation. Another aspect is that the infrastructure manager's administrative framework currently makes it impossible to compare costs in contracts with final cost, meaning that there is no institutionalized learning process in place. Design preparations and the estimation of costs for new projects must therefore be done without an understanding of what has been working well in the implementation of previous projects. While Benefit-Cost Analysis (BCA) played no role in the planning of the seven projects, the article sends a stark warning that early cost estimates provide poor input for assessing project rate of return.
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9.
  • Ridderstedt, Ivan, 1990-, et al. (författare)
  • Economies of scale versus the costs of bundling in the procurement of highway pavement replacement
  • 2022
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Although most public procurements involve decisions concerning bundling there is only a limited body of empirical research guiding policy on this matter. In this paper, we examine the cost effects of pure bundling in the competitive tendering of highway pavement replacement with hot-mix asphalt. For this we use linear regression on data from a comprehensive sample of such contracts procured by the Swedish infrastructure manager (IM) during the period 2012–2015. We find that bundling affects the procurer’s cost in multiple and partly counteracting ways. Our results show that economies of scale are strong but diminishing and counteracted by costs of bundling and bundling related factors. Overall, the findings support Swedish IM’s current design of bundles but also suggest that most of the contracts are still inefficiently small. Whilst not perfectly generalizable to other markets, the findings provide some support the increased promotion and use of bundling of small-scaled road rehabilitation projects in the US. Two main implications of the results are that bundling policy should emphasize proximity and similarity rather than whether work is small-scale and that the scope for efficient bundling should be accounted for when optimizing the timing of pavement replacement.
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10.
  • Nilsson, Jan-Eric, 1952-, et al. (författare)
  • Kontrakt för underhållsbeläggningar : analyser av produktivitet, effektivitet och kostnadsförändringar mellan avtal och slutkostnader
  • 2021
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • Varje år genomför Trafikverket beläggningsarbeten för att upprätthålla en acceptabel standard på längre vägsträckor för närmare tre miljarder kronor. Rapporten sammanfattar resultatet av tre analyser som gjorts av denna typ av upphandlingar. Både projektkostnaden i kontraktet mellan Trafikverket och en entreprenör och den slutligt fakturerade kostnaden behandlas. Syftet är att identifiera möjligheter att vidareutveckla verksamhetens produktivitet och effektivitet. Varje procentenhets kostnadsbesparing kan frigöra betydande medel för att beställa mer underhåll eller för att överföras till andra, mera angelägna ändamål. Den första delstudien pekar på möjligheter att effektivisera de beläggningsarbeten där varma beläggningar appliceras. Analyser av kostnaden för 293 sådana kontrakt visar att det finns starka skäl att överväga att göra kontrakten större än idag. Ju fler kvadratmeter beläggning som ingår i varje kontrakt, desto lägre är kostnaden per kvadratmeter. Den andra delstudien försöker förklara varför slutkostnaden i genomsnitt är 14 procent högre än kostnaden i de kontrakt som tecknats medan den tredje studien redovisar en produktivitetsanalys av samma kontrakt. Trots att flera hundra beläggningskontrakt upphandlats under den aktuella tidsperioden har enbart 91 observationer funnits tillgängliga för analys. Förklaringen är att det inte är möjligt att koppla samman den verksamhet som upphandlats med slutresultatet av uppdragen. Detta gäller både verksamhetens kostnader och mängden faktiskt nedlagt arbete som kan skilja sig från de beställningar som görs. Den slutliga granskningen av rapporten har också visat på brister i matchningen mellan kontrakts- och slut kostnad, vilket innebär att det inte är möjligt att redovisa några policyslutsatser. Analyserna illustrerar emellertid hur uppföljningar kan genomföras för att fördjupa förståelsen av bland annat kostnadsavvikelser.
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