| 1. |
- Hassler, John, et al.
(författare)
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SNS Economic Policy Council Report 2020 : Swedish Policy for Global Climate
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Climate policy is a complex area that requires input from many different perspectives. The sns Economic Policy Council 2020 comprises nine researchers from a range of disciplines, with different backgrounds and with varied opinions on the debate surrounding climate policy. They analyse Swedish climate policy in a global context, describing the causes and consequences of climate change and focusing on how policy can achieve the desired reductions in carbon emissions. The report also provides answers to questions that are frequently discussed in the Swedish debate, such as the effectiveness of climate aid and whether Sweden should generate a larger surplus of fossil-free electricity for export.
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| 2. |
- Hassler, John, et al.
(författare)
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Svensk politik för globalt klimat
- 2020
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Nio forskare från olika discipliner ingår i SNS Konjunkturråd 2020. Forskarna har bred bakgrund inom nationalekonomi, juridik, naturvetenskap och ingenjörsvetenskap. Tillsammans har de skrivit SNS Konjunkturrådsrapport 2020: Svensk politik för globalt klimat, där de fokuserar på hur politiken ska utformas för att bromsa och till slut stoppa klimatförändringarna. Några av deras viktigaste förslag och rekommendationer: Låt kolet stanna i marken. Det är kolet, inte konventionell olja, som är det centrala hotet mot klimatet. Om klimatförändringarna ska hejdas måste Kina bli av med sitt kolberoende. Indien och Afrika kan inte heller följa Kinas kolkraftsbaserade utvecklingsstrategi. Merparten av världens kolreserver måste stanna i marken.Inför globalt minimipris på koldioxidutsläpp och slopa fossilsubventioner. Det är två nödvändiga ingredienser i klimatpolitiken som måste diskuteras på FN:s nästa stora klimatkonferens COP26 i Glasgow.Gröna subventioner räcker inte för att minska utsläppen. Billig grön energi leder till ökad användning av sådan men inte automatiskt till att fossila bränslen utkonkurreras.Bidra till rätt global inriktning. Den svenska klimatpolitiken bör ha som överordnat mål att minska de globala utsläppen.Bidra finansiellt till andra länders omställning. Klokt och välavvägt klimatbistånd är både möjligt och önskvärt. Inom ramen för EU:s klimatpolitik finns fungerande sätt att finansera mindre rika medlemsländers utsläppsminskningar. Men eftersom även Sverige måste bli klimatneutralt bör ett ökat klimatbistånd inte minska de svenska klimatambitionerna.Klimatklubbar. Sverige bör driva frågan om att det ska vara tillåtet att införa klimattullar mot länder som inte har en acceptabel nivå på utsläppspriset. En modell är så kallade klimatklubbar där länder går ihop och sätter ett enhetligt utsläppspris. Import från länder som inte deltar i klubben beläggs med en tull.Fossilfri elexport kan ge betydande minskningar av utsläppen inom EU genom att pressa undan kolkraft där sådan fortfarande används.Finansiera insamling och lagring av koldioxid (CCS-teknik) med lagringspeng. Vi kan ta hand om koldioxid motsvarande hälften av Sveriges utsläpp till en kostnad motsvarande det som dras in till staten via koldioxidskatten. Det krävs dock en statlig finansiering som bör utformas som ett bidrag per ton insamlad och säkert lagrad koldioxid:– Motsvarande runt hälften av Sveriges koldioxidutsläpp kan tas bort om CCS-tekniken införs på de 27 industrianläggningar som släpper ut mest i Sverige. Detta är mer än utsläppen från hela den svenska vägtrafiken. Tekniken fungerar också i resten av världen och Sverige kan här bli ett föregångsland, säger John Hassler, ordförande i SNS Konjunkturråd 2020.
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| 3. |
- Oldgren, Jonas, 1964-, et al.
(författare)
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Systematic Coronary Risk Evaluation estimated risk and prevalent subclinical atherosclerosis in coronary and carotid arteries: A population-based cohort analysis from the Swedish Cardiopulmonary Bioimage Study
- 2021
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Ingår i: European Journal of Preventive Cardiology. - : Oxford University Press (OUP). - 2047-4873 .- 2047-4881. ; 28:3, s. 250-259
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Tidskriftsartikel (refereegranskat)abstract
- Background It is not clear if the European Systematic Coronary Risk Evaluation algorithm is useful for identifying prevalent subclinical atherosclerosis in a population of apparently healthy individuals. Our aim was to explore the association between the risk estimates from Systematic Coronary Risk Evaluation and prevalent subclinical atherosclerosis. Design The design of this study was as a cross-sectional analysis from a population-based study cohort. Methods From the general population, the Swedish Cardiopulmonary Bioimage Study randomly invited individuals aged 50-64 years and enrolled 13,411 participants mean age 57 (standard deviation 4.3) years; 46% males between November 2013-December 2016. Associations between Systematic Coronary Risk Evaluation risk estimates and coronary artery calcification and plaques in the carotid arteries by using imaging data from a computed tomography of the heart and ultrasonography of the carotid arteries were examined. Results Coronary calcification was present in 39.5% and carotid plaque in 56.0%. In men, coronary artery calcium score >0 ranged from 40.7-65.9% and presence of carotid plaques from 54.5% to 72.8% in the age group 50-54 and 60-65 years, respectively. In women, the corresponding difference was from 17.1-38.9% and from 41.0-58.4%. A doubling of Systematic Coronary Risk Evaluation was associated with an increased probability to have coronary artery calcium score >0 (odds ratio: 2.18 (95% confidence interval 2.07-2.30)) and to have >1 carotid plaques (1.67 (1.61-1.74)). Conclusion Systematic Coronary Risk Evaluation estimated risk is associated with prevalent subclinical atherosclerosis in two major vascular beds in a general population sample without established cardiovascular disease or diabetes mellitus. Thus, the Systematic Coronary Risk Evaluation risk chart may be of use for estimating the risk of subclinical atherosclerosis.
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| 4. |
- Westin, Jonas, 1980-
(författare)
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Efficiency and acceptability of pricing policies and transport investments in distorted economies
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis contains five papers studying the economic efficiency and political acceptability of road pricing policies and transport investments in distorted economies. Interactions between the transport market and other distorted markets, such as the labor market, can have a large impact on the welfare effect of a road pricing policy or a transport investment. Many road pricing studies therefore try to incorporate effects from other distorted markets in the analysis. Paper I analyzes how the economic efficiency of a road toll in a distorted economy depends on assumptions about the initial tax system. In the road pricing literature, the welfare effect of a road toll is often found to depend on revenue use. Using a simple general equilibrium model paper I shows that the relative efficiency of marginal revenue recycling policies depends more on assumptions regarding inefficiencies in the initial tax system than on the road toll per se. Paper II studies the effect on welfare, equity and labor supply from a road toll in a commuting population with heterogeneous value of time and endogenous labor supply. When explicitly taking into account that commuters have different value of time, the road toll can increase total labor supply even when the revenues are not recycled back to the commuters. The analysis stresses the importance of recognizing traveler heterogeneity when analyzing congestion pricing. Road pricing policies are often characterized by conflicting interests between different stakeholders and different geographical areas. Papers III and IV study the economic efficiency and political acceptability of pricing and investment policies in different institutional and geographical settings. The main contribution of the papers is to explain how political constraints can lead to inefficient tolling strategies. The papers contribute to the existing literature on political acceptability of road pricing by analyzing the conflict and potential trade-off between political acceptability and economic efficiency. A difficulty when assessing the welfare effect of a future transport policy is also that many factors and parameters needed for the analysis are uncertain. Paper V studies the climate benefit of an investment in high speed rail by calculating the magnitude of annual traffic emission reduction required to compensate for the annualized embedded emissions from the construction of the line. The paper finds that to be able to balance the annualized emissions from the construction, traffic volumes of more than 10 million annual one-way trips are usually required, and most of the traffic diverted from other transport modes must come from aviation.
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| 5. |
- Ait Ali, Abderrahman, 1991-, et al.
(författare)
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A disaggregate bundle method for train timetabling problems
- 2020
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Ingår i: Journal of Rail Transport Planning & Management. - : Elsevier BV. - 2210-9706 .- 2210-9714. ; 16
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Tidskriftsartikel (refereegranskat)abstract
- The train timetabling problem (TTP) consists of finding a feasible timetable for a number of trains which minimises some objective function, e.g., sum of running times or deviations from ideal departure times. One solution approach is to solve the dual problem of the TTP using so-called bundle methods. This paper presents a new bundle method that uses disaggregate data, as opposed to the standard bundle method which in a certain sense relies on aggregate data. We compare the disaggregate and aggregate methods on realistic train timetabling scenarios from the Iron Ore line in Northern Sweden. Numerical results indicate that the proposed disaggregate method reaches better solutions faster than the standard aggregate approach.
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| 6. |
- Ait-Ali, Abderrahman, 1991-, et al.
(författare)
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Are commuter train timetables consistent with passengers’ valuations of waiting times and in-vehicle crowding?
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Many models have been developed and used to analyse the costs and benefits of transport investments. Similar tools can also be used for transport operation planning and capacity allocation. An example of such use is the assessment of commuter train operations and service frequency. In this study, we analyse the societally optimal frequency for commuter train services. The aim is to reveal the implicit valuation (by the public transport agency) of the waiting time and the in-vehicle crowding in the commuting system. We use an analytic CBA model to formulate the societal costs of a certain service frequency and analyse the societally optimal frequencies during peak and off-peak hours. Comparing the optimal and the actual frequencies allows to reveal the implicit valuations of waiting time and crowding. Using relevant data from the commuter train services in Stockholm on a typical working day in September 2015 (e.g., OD matrix, cost parameters), we perform a numerical analysis on certain lines and directions. We find the societally optimal frequency and the implicit valuation of waiting time and crowding. The results suggest that the public transport agency in Stockholm (i.e., SL) adopted service frequencies that are generally slightly higher than societally optimum which can be explained by a higher implicit valuation of waiting time and crowding. We also find that the optimal frequencies are more sensitive to the waiting time valuation rather than that of crowding.
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| 7. |
- Ait-Ali, Abderrahman, 1991-, et al.
(författare)
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Are commuter train timetables consistent with passengers’ valuations of waiting times and in-vehicle crowding?
- 2022
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Ingår i: Transport Policy. - : Elsevier BV. - 0967-070X .- 1879-310X. ; 116, s. 188-198
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Tidskriftsartikel (refereegranskat)abstract
- Social cost-benefit analysis is often used to analyse transport investments, and can also be used for transport operation planning and capacity allocation. If it is to be used for resolving capacity conflicts, however, it is important to know whether transit agencies' timetable requests are consistent with the cost-benefit framework, which is based on passenger preferences. We show how a public transport agency's implicit valuations of waiting time and crowding can be estimated by analysing timetables, apply the method to commuter train timetables in Stockholm, and compare the implicit valuations to the corresponding passenger valuations in the official Swedish cost-benefit analysis guidelines. The results suggest that the agency puts a slightly lower value on waiting time and crowding than the passenger valuations codified in the official guidelines. We discuss possible reasons for this and implications for using cost-benefit analysis for capacity allocation. We also find that optimal frequencies are more sensitive to the waiting time valuation than to that of crowding.
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| 8. |
- Ait Ali, Abderrahman, 1991-, et al.
(författare)
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Disaggregation in Bundle Methods : Application to the Train Timetabling Problem
- 2017
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Konferensbidrag (refereegranskat)abstract
- Bundle methods are often used to solve dual problems that arise from Lagrangian relaxations of large scale optimization problems. An example of such problems is the train timetabling problem. This paper focuses on solving a dual problem that arises from Lagrangian relaxation of a train timetabling optimization program. The dual problem is solved using bundle methods. We formulate and compare the performances of two different bundle methods: the aggregate method, which is a standard method, and a new, disaggregate, method which is proposed here. The two methods were tested on realistic train timetabling scenarios from the Iron Ore railway line. The numerical results show that the new disaggregate approach generally yields faster convergence than the standard aggregate approach.
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| 9. |
- Ait Ali, Abderrahman, 1991-, et al.
(författare)
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European Railway Deregulation : An overview of market organization and capacity allocation
- 2022
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Ingår i: Transportmetrica A. - : Taylor & Francis. - 2324-9935 .- 2324-9943. ; 18:3, s. 594-618
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Tidskriftsartikel (refereegranskat)abstract
- Railway markets in Europe have been reorganized to allow competition between different operators. Thus, European railways have been vertically separated, separating infrastructure management from provisions of train services. This allows several train operators to compete for passengers and freight services. Different ways have emerged for vertical separation, capacity allocation and track access charges. This paper reviews, compares and discusses important deregulation aspects, using examples from a number of European countries to show different possible solutions. The study describes how competition has been introduced and regulated, with a particular focus on describing the different ways capacity is allocated and how conflicting requests by different train operators are resolved. It also reviews the related issue of how access charges are constructed and applied. Although guided by the same European legislation, we conclude that the studied railways have different deregulation outcomes, e.g., market organization, capacity allocation. Besides, few countries have so far managed to create efficient and transparent processes for allocating capacity between competing train operators. Although allowed by the legislation, market-based allocation is absent or never used. In order to foster more competition which can yield substantial social benefits, the survey indicates that most European railways still need to develop and experiment with more efficient and transparent capacity allocation procedures.
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| 10. |
- Ait Ali, Abderrahman, 1991-, et al.
(författare)
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Measuring the Socio-economic Benefits of Train Timetables : Application to Commuter Train Services in Stockholm
- 2017
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Ingår i: 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary. - : Elsevier. ; , s. 849-856
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Konferensbidrag (refereegranskat)abstract
- On highly used railway lines with heterogeneous traffic, timetabling is challenging. In particular, the limited existing capacity means that to guarantee an acceptable level of quality, the infrastructure manager must cancel some train services on the expense of others. In this article, we study the conflict between commercial long-distance trains and subsidized commuter trains with a socio-economic perspective (i.e. travelers and train operators). The study attempts to answer the following question: What is the socio-economic effect of modifying the timetable of a commuter service?The case study treats the commuter train services in Stockholm. Trip data was collected from the local commuter train operator. An entropy maximization-based model was implemented to estimate the dynamic network Origin-Destination (OD) matrix. This dynamic matrix, of one full working day, was then used to estimate the number of travelers per train, and further converted for use in the microscopic simulation tool RailSys. Travel and waiting time are estimated for each OD pair and with that the generalized costs for the travelers and operators. The effect of crowding in the trains is included in the estimation. The article can be considered as an initiation to a novel method to calculate effects of changes in commuter train timetables. This novel approach enables to price commercial train slots in the capacity allocation process such as in an auction. It provides a new way to estimate the local train operator´s valuation of the different parameters (i.e. waiting, travel time and interchanges). Using RailSys for the estimation of times makes it possible to include capacity aspects that normally are difficult to reveal.
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