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on Transport Economics |
| By: | T. MAYER (Sciences-Po,CEPII et CEPR); T. TREVIEN (Insee) |
| Abstract: | Evaluating the impact of transport infrastructure meets a major challenge since rail lines are not randomly located. We use the natural experiment offered by the opening and progressive extension of the Regional Express Rail (RER) between 1970 and 2000 in the Paris metropolitan region, and in particular the deviation from original plans due to budgetary constraints and technical reasons, in order to identify the causal impact of urban rail transport on firm location, employment and population growth. We use a difference-in-differences approach on a specific subsample, selected to avoid endogeneity bias which occurs when evaluating transportation effects. We find that the increase in employment is 12.8% higher in municipalities connected to the new network compared to the existing suburban rail network. Places located within 20 km from Paris are the only affected. While we find no effect on overall population growth, our results suggest that the commissioning of the RER may have increased the competition for land since high-skilled households are more likely to locate in the vicinity of a RER station. |
| Keywords: | Public policy evaluation, Public transportation, Firm and household location choices |
| JEL: | D04 H43 R42 |
| Date: | 2015 |
| URL: | http://d.repec.org/n?u=RePEc:crs:wpdeee:g2015-03&r=all |
| By: | Mark WARDMAN |
| Abstract: | The experience of transport systems users, in terms of comfort, reliability, safety and above all convenience, is critical in determining demand for transport services, at least when there is a choice of alternative ways to travel. Convenience is one of the strongest attractions of the private car for passenger transport. For users of public transport, convenience is also clearly important but not always clearly defined and not often measured in designing transport systems or monitoring their operating performance. In many situations, an increase in public transport convenience reduces the unit costs of travel (euros/dollars per hour or cents per minute) and so provides benefits equivalent to an increase in travel speed. This report focuses on convenience and its importance to the user experience. It reviews operational definitions of convenience, evidence for the willingness of users to pay for convenience and the use of indicators to assess and improve the convenience of public transport, with a view to making it more effective and more competitive. |
| Date: | 2014–05–13 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/2-en&r=all |
| By: | Vincent Viguié (CIRED - Centre International de Recherche sur l'Environnement et le Développement - EHESS - École des hautes études en sciences sociales - AgroParisTech - CIRAD - Centre de coopération internationale en recherche agronomique pour le développement - École des Ponts ParisTech (ENPC) - CNRS); Stéphane Hallegatte (World Bank - World Bank) |
| Abstract: | In a context of rapid urbanization and energy transition, massive investments will be required to develop efficient public transport networks. Capturing the increase in land value caused by transport infrastructure (for example, through a betterment tax) appears a promising way to finance public transport. However, it is no trivial task, as it is difficult to anticipate the rent creation. This paper uses a simple city model based on urban economic theory to compute the rent created by improvements in public transport infrastructure in Paris, France. To apply in places where models or data are not available, a reduced form of the model is shown to provide acceptable approximations of the rent creation. Simulations confirm that land value capture can finance a significant part of transport investments. The simulations also show that value capture potentials are influenced by what happens in the entire agglomeration. Simultaneous infrastructure investments in different parts of the city play a significant role, as they change overall accessibility patterns. Evolutions taking place in other cities also have a comparable influence. Non-local effects can change the total potential for land value capture and multiply this potential by as much as a factor of two. |
| Date: | 2015–03–26 |
| URL: | http://d.repec.org/n?u=RePEc:hal:ciredw:hal-01136199&r=all |
| By: | Benedikt Mandel |
| Abstract: | This paper describes the econometric system approach developed by MKmetric to perform short and long-term air transport demand forecasts while considering various determinants such as socio-economy, policy, infrastructure and land use. The necessities for modelling air transport evoking from a transport system point of view and the changes of the aviation world occurred during the last decade are investigated. Based on these findings the mathematical framework is outlined considering shortfalls of traditional models used in aviation forecasting and restrictions caused by classical functional forms. The increasing gap of information for modelling is described and alternative data sources used for the development of the system approach are listed. As all models are imperfect describing just a part of real life, it sheds a light on the necessity to validate models and the prerequisite of complexity needed to cope with multi-sector scenario simulations for strategic, tactical and operational developments as well as political decisions. Finally some analysis examples demonstrate the power of the approach used focusing on the choice modelling reflecting consumers’ behaviour. |
| Keywords: | consumer behaviour |
| Date: | 2014–04 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/7-en&r=all |
| By: | Weiner, Jennifer |
| Abstract: | Many of the region's roads and bridges are in need of significant repair and improvement. There is concern that current revenue sources are inadequate relative to the projected expense of maintaining and keeping New England's roads, bridges, and other transportation assets in good condition. How to address the projected gap in transportation revenues and expenditures is largely a policy choice. Most states rely on the motor fuel excise tax or "gas tax" but this revenue source is widely recognized as not fiscally sustainable. The tax does not automatically grow with inflation, whereas the costs associated with maintaining, constructing, and reconstructing roads tend to increase as prices and wages rise. And, as vehicle fuel efficiency increases, the gas tax will generate less revenue for a given amount of road use than in the past. This research compares existing gas taxes in the New England states and examines alternative tax structures that could improve fiscal sustainability. It simulates tax revenues under various alternatives and compares them to estimates of revenues generated by actual gas taxes in the New England states between 1993 and 2012. Forward-looking projections for selected alternatives are also provided. |
| Date: | 2015–08–01 |
| URL: | http://d.repec.org/n?u=RePEc:fip:fedbpr:2015_001&r=all |
| By: | Geetam Tiwari |
| Abstract: | Safe travel for all road users is a prerequisite for ensuring sustainable and inclusive cities. Providing safe transport system is an objective for sustainable transport, because risk of injuries and deaths from traffic crashes has become a major public health concern worldwide (WHO, 2011). At the same time safety of pedestrians, bicyclists and public transport users also has an impact on the choice of these modes. Risk to pedestrians, bicyclists and public transport users can be reduced by appropriate street designs and neighbourhood environment. Safer pedestrian and bicycle infrastructure results in increased use of these environment friendly modes (Tiwari & Jain, 2012). Safe travel options for women in general and specifically low income women are important for addressing livelihood and poverty issues for a significant proportion of urban population in low income countries like India. In this paper we present data from two Indian cities- Vishakhapattanam( a city in south India with a population of 1.7 million persons) and Delhi the capital city of India having 16.4 million residents to compare the travel patterns of women and men. The household survey in Delhi focused on low income settlements since poverty adds another dimension to gender bias. The survey repeated after ten years shows that the travel patterns remain unchanged. Women travel shorter distances, are dependent on lower cost modes-walking and public transport and perform multi-purpose linked trips. In view of the sustainability requirements, lower mobility of women must be addressed by ensuring safe accessibility to employment opportunities by walking, bicycles and public transport. The paper concludes with possible interventions required to ensure safe and secure travel of women at land use planning level and street design level. |
| Date: | 2014–04–16 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/4-en&r=all |
| By: | Björklund, Gunilla (VTI); Swärdh, Jan-Erik (VTI) |
| Abstract: | The purpose of the present study is to estimate the WTP for comfort, i.e. to get a seat, and crowding reduction on board local public transport in Sweden, including the modes metro, tram, commuter train, and local bus. We use data from a stated preference-study conducted in the three largest urban areas of Sweden. Respondents were recruited both during a trip and from a web panel. The stated preference-questions consisted of four attributes: travel cost, travel time, seating or standing during the trip, and crowding level. Crowding level was illustrated by pictures showing different number of standing travelers per square meter. The estimated results suggest a WTP for seating of SEK 30 to 37 (SEK 10 approximately equal EUR 1) per hour depending on the crowding level. A reduction to no standing passengers from 4 and 8 standing passengers per square meter is valued SEK 12-13 and 27-32 respectively, depending on seating or standing condition. A reduction to no standing passengers from 1 standing passenger per square meter is not worth anything when the traveler is seating but SEK 8 when the traveler is standing. If we instead interpret our estimated results as value of travel time saving-multipliers, the worst travel condition in our study, i.e. standing in a crowding of 8 standing passengers per square meter, has a multiplier of about 2.1. All in all, our results seem plausible as they lies in the middle of comparable estimated results from earlier studies that have valuated comfort and crowding reductions. Finally, sensitivity analysis also show that the results seem to be both robust and in line with value of travel time savings-knowledge. |
| Keywords: | Public transport; Comfort; Crowding; Willingness to pay; Value of travel time savings |
| JEL: | C25 R41 |
| Date: | 2015–09–02 |
| URL: | http://d.repec.org/n?u=RePEc:hhs:ctswps:2015_012&r=all |
| By: | P. GIVORD (Insee); C. GRISLAIN-LETRÉMY (Insee); H. NAEGELE (DIW) |
| Abstract: | This paper sets out to identify the impact of fuel prices on new car purchases, using exhaustive individual-level data of monthly registration of new private cars in France from 2003 to 2007. Detailed information on the car holder enables us to account for heterogeneous preferences across purchasers. We identify demand parameters through the large oil price fluctuations of this period. We find that the sensitivity of short-term demand with respect to fuel prices is generally low. Using these estimates, we assess the impact of a policy equalizing diesel and gasoline taxes, assuming that consumers react similarly to fuel price changes from tax and from oil price variations. Such a policy would slightly reduce the share of diesel in new cars purchases in the short-run (i.e. before supply side adjustments take place), without substantially changing the average fuel consumption or CO2 emission levels of new cars. Alternatively, a carbon tax (at 15 ¬/ton of CO2) could slightly decrease these emissions in the short-run. |
| Keywords: | fuel prices, automobiles, carbon dioxide emissions, environmental tax |
| JEL: | C25 D12 H23 L62 Q53 |
| Date: | 2014 |
| URL: | http://d.repec.org/n?u=RePEc:crs:wpdeee:g2014-14&r=all |
| By: | Hironori Kato |
| Abstract: | Promoting public transportation, which includes rail, metro, bus rapid transit, and bus services is one of the most popular urban transportation policies among transportation authorities in many countries. This popularity may reflect the social requirement to pursue a sustainable transportation system by motivating people to use an environmentally friendly transportation mode. In particular, the modal shift from the automobile to public transportation is highlighted in urban transportation planning because many cities have suffered from serious traffic congestion, which has caused economic losses as well as negative impacts on local, regional, and global environments. In order to attract individuals to use public transportation, the improvement of service is critical. This includes increasing service frequency, decreasing travel time, upgrading station facilities, and introducing higher-capacity vehicles. |
| Date: | 2014–04–14 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/1-en&r=all |
| By: | Andersson, Henrik (Toulouse School of Economics (LERNA)); Swärdh , Jan-Erik (VTI); Ögren , Mikael (Göteborg university) |
| Abstract: | Valuation of traffic noise abatement based on hedonic pricing models of the property market has traditionally measured the noise as the equivalent, or another average, level. What is not captured in such a noise indicator is the maximum noise level of a vehicle passage. In this study, we incorporate the maximum noise level in the hedonic model letting the property price depend on both the equivalent noise level and the maximum noise level. Hedonic models for both rail and road noise are estimated. Data consists of characteristics of sold properties, property-specific noise calculation, and geographical variables. We use the hedonic approach to estimate the marginal willingness to pay (WTP) for maximum noise abatement where we model the effect as the maximum noise level subtracted with the equivalent noise level. Furthermore, we control for the equivalent noise level in the estimations. The estimated results show that including the maximum noise level in the model has influence on the property prices, but only for rail and not for road. This means that for road we cannot reject the hypothesis that WTP for noise abatement is based on the equivalent noise level only. For rail, on the other hand, we estimate the marginal WTP for the maximum noise level and it turns out to be substantial. Also, the marginal WTP for the equivalent noise levels seems to be unaffected by the inclusion of the maximum noise level in the model. More research of this novel topic is requested though. |
| Keywords: | Noise; Hedonic regression; Rail; Road; Equivalent level; Maximum level |
| JEL: | C21 C26 Q51 Q53 |
| Date: | 2015–08–21 |
| URL: | http://d.repec.org/n?u=RePEc:hhs:ctswps:2015_011&r=all |
| By: | Wang, X.; Agatz, N.A.H.; Erera, A. |
| Abstract: | Dynamic ride-sharing systems enable people to share rides and increase the efficiency of urban transportation by connecting riders and drivers on short notice. Automated systems that establish ride-share matches with minimal input from participants provide the most convenience and the most potential for system-wide performance improvement, such as reduction in total vehicle-miles traveled. Indeed, such systems may be designed to match riders and drivers to maximize system performance improvement. However, system-optimal matches may not provide the maximum benefit to each individual participant. In this paper we consider a notion of stability for ride-share matches and present several mathematical programming methods to establish stable or nearly-stable matches, where we note that ride-share matching optimization is performed over time with incomplete information. Our numerical experiments using travel demand data for the metropolitan Atlanta region show that we can significantly increase the stability of ride-share matching solutions at the cost of only a small degradation in system-wide performance. |
| Keywords: | ride-sharing, carpooling, sustainable transport, stable matching |
| Date: | 2015–05–27 |
| URL: | http://d.repec.org/n?u=RePEc:ems:eureri:78193&r=all |
| By: | Hironori Kato |
| Abstract: | Tokyo is well known as a rail-oriented city where the huge traffic demand generated from the megacity is well supported by a sophisticated urban rail system. The results of the 2008 Person Trip Survey show that rail’s modal share was 30% as of 2008; the economy of Tokyo is highly dependent on an efficient urban rail network. As shown in Kato (2014), Tokyo’s urban rail market has unique characteristics: private rail companies provide many of the rail services, the rail network was developed under the guidance of the central government, rail users suffered from chronic traffic congestion for many years, and the rail market has recently been significantly influenced by a rapidly aging demographic. In spite of its uniqueness, the experiences of urban rail development in Tokyo could be useful for other OECD member countries. |
| Date: | 2014–04–16 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/5-en&r=all |
| By: | César Ducruet; Hidekazu Itoh; Olaf Merk |
| Abstract: | The ability of ports to ensure efficient cargo transfers is one central dimension of their overall function as transport nodes. Before containerization, such as in the late nineteenth century, large seaports were already competing in their attempt providing fast transit between sea and land, in a context of growing global trades (Marnot, 2012). Such aspects are even more crucial nowadays when the port can be considered as only one element of value-driven supply chains (Robinson, 2002) or as a set of independent terminals operated by global actors (Olivier and Slack, 2006). While port efficiency as a whole may be understood from various perspectives, its influence on trade facilitation (Clark et al., 2004) and regional development (Haddad et al., 2010) has been well underlined. Ways to measure port efficiency and performance are very diverse, but the time factor has been so far largely left aside, especially in international comparative studies of ports. More frequent are case studies of specific aspects such as fast-ship services (De Langen, 1999), broader approaches such as the global synchronization of transport terminals in a context of space/time collapse (Rodrigue, 1999), or operations research about queuing models of vessels in relation to port entrance channels and berth allocation and productivity. |
| Date: | 2014–08 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/8-en&r=all |
| By: | Olaf Merk |
| Abstract: | Ports are no longer perceived as main drivers of urban economic development. A variety of factors have been identified in the academic literature to contribute to urban economic growth, ranging from human capital, entrepreneurial culture, diversity and infrastructure to planning and governance. Port infrastructure is in many cases not even considered as a potential source of economic development. Whereas efficient ports have contributed to a substantial reduction in transportation costs, and thus stimulated external trade and related economic development, the general perception is that most of the gains of external trade have spread out to other regions than the port area or the port region (e.g. Gripaios and Gripaios, 1995). This is related to de-concentration of logistics activity and “port regionalisation” tendencies (Notteboom and Rodrigue, 2005). In contrast, negative impacts related to ports have unevenly affected port-cities, including socio-economic impacts related to a unskilled workforce needed to sustain a port-industrial complexes that have ceased to be labour-intensive. Economic benefits of ports were less ambiguous in the past, when port-cities dominated trade-oriented emerging capitalist economies, as eloquently described in Braudel (1979). |
| Date: | 2014–08 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/9-en&r=all |
| By: | Mary R. Brooks; Thanos PALLIS; Stephen Perkins |
| Abstract: | Ports around the globe are planning expansions to respond to the growth of containerised maritime trade and to the development needs of their hinterland economies. Following the dip in trade induced by the 2007-2008 financial crisis, global volumes are on the rise again (Figure 1), driven by growth in the emerging economies. Growth in trade will be supported by the WTO Trade Facilitation Agreement signed in Bali in December 2013 and expanding container port capacity is again a pressing issue in many locations. Inadequate container port infrastructure can be a severe logistics bottleneck and a constraint on growth. Efficiency and capacity need to increase in step with demand. At the same time port policy makers and container terminal operators have to match capacity to demand carefully to avoid costly overinvestment, a task complicated by rapid technological change in liner shipping markets with the introduction of larger vessels, rising fuel prices and restructuring through mergers and alliances. |
| Date: | 2014–04–11 |
| URL: | http://d.repec.org/n?u=RePEc:oec:itfaab:2014/3-en&r=all |
| By: | Howell, Sabrina (Harvard University); Lee, Henry (Harvard University); Heal, Adam (Harvard University) |
| Abstract: | China has ambitious goals for developing and deploying electric vehicles (EV). The stated intention is to "leapfrog" the auto industries of other countries and seize the emerging EV market. Since 2009, policies have included generous subsidies for consumers in certain locations, as well as strong pressure on local governments to purchase EVs. Yet four years into the program, progress has fallen far short of the intended targets. China's EV industry faces the same challenges as companies in the West: a) high battery costs; b) inadequate range between charges; and c) no obvious infrastructure model for vehicle charging. In addition, China's industry is constrained by four domestic barriers. Mass EV deployment in China likely requires substantial policy adjustment. In particular, it will be necessary to permit foreign EV technologies relatively free market entry. In turn, this requires greater foreign IP protection. China must also consolidate its domestic industry and place greater emphasis on smaller, cheaper vehicles aimed at domestic, lower-end markets. If EVs are to contribute to air quality improvement, the government must ensure that the electricity powering EVs is cleaner than the current mix, particularly in Northeast regions of China. |
| Date: | 2014–07 |
| URL: | http://d.repec.org/n?u=RePEc:ecl:harjfk:rwp14-035&r=all |
| By: | Christian Vonbun |
| Abstract: | Este Texto para Discussão (TD) apresenta uma breve revisão da literatura acerca dos custos e benefícios de veículos elétricos e veículos híbridos do tipo plug-in (PHEV), com ênfase em seus benefícios em termos de redução da emissão de gases de efeito estufa e gases nocivos à saúde humana. Conclui-se que os veículos híbridos, ainda que tenham de superar barreiras tecnológicas e culturais, apresentam um grande potencial de elevar não apenas a eficiência energética do setor de transporte, mas também contribuir para aumentar a eficiência e reduzir os custos relacionados à produção de energia elétrica. Esses veículos podem servir de ponte entre os veículos convencionais e os elétricos, quando os desenvolvimentos tecnológicos, notadamente relativos ao custo e à eficiência das baterias permitirem a adoção generalizada de veículos elétricos. Todavia, é importante notar que o aproveitamento pleno do potencial de economia e de redução de emissão de poluentes está condicionado à implantação das chamadas smart grids e, mais importante, de como se configura a produção marginal de energia elétrica na região e no período considerados. This paper presents a brief literature review concerning the costs and benefits of electric vehicles and hybrid electric vehicles, highlighting their advantages in terms of greenhouse gas emissions reductions. Even though electric and electro-hybrid vehicles must still overcome many cultural and technological barriers, they present a great potential in improving the energy efficiency of the transportation system, as well as reducing the costs of electric energy production and transmission. The hybrid vehicles may close the technological and operational gap between the old internal combustion powered vehicles and the new electric cars, until new improvements on batteries allow the widespread introduction of electric cars as the standard individual transportation vehicles. Nevertheless, it is imperative to stress that the full potential benefits of these vehicles is conditioned to the implementation of Smart Grids that enable the electric system to use them as a reservoire of energy that provides back up power to the system, to be employed in peak consumption hours. It is also vital to ensure that the required incremental energy production is proportionately cleaner than the internal combustion vehicles they replace. |
| Date: | 2015–08 |
| URL: | http://d.repec.org/n?u=RePEc:ipe:ipetds:2123&r=all |
| By: | Björklund, Gunilla (VTI); Wallén Warner, Henriette (VTI) |
| Abstract: | The first aim of the present study was to investigate the moderating effects of safety skills on the relationship between perceptual-motor skills and risky driving behaviours (i.e. speeding in urban areas, speeding in rural areas and tendencies to overtake). The second aim was to examine the moderating effects of safety skills on the relationship between irritations evoked by different driving behaviours (i.e. progress impeded, reckless driving and direct hostility) and expressed irritation by same behaviours. A sample of 100 Swedish drivers completed a questionnaire including the Driver Skill Inventory (DSI), a Swedish version of the Driving Anger Scale (Swe-DAS), as well as questions about expressed irritation and risky driving behaviours. The results showed that safety skills made significant contributions to the prediction of risky driving behaviours (i.e. speeding in urban areas, speeding in rural areas and tendencies to overtake) so that higher safety skills was associated with less risky driving behaviours. Irritation evoked by different driving behaviours (i.e. progress impeded, reckless driving and direct hostility) made significant contributions to the prediction of expressed irritation by the same behaviours, so that higher levels of irritation were associated with more often expressed irritation. No moderation effects of safety orientation could be found on risky driving behaviours or on irritation in traffic, with the exception of a small interaction effect between safety skills and irritation evoked by progress impeded. |
| Keywords: | Safety skills; Perceptual-motor skills; Risky driving behaviours; Irritation; Driver Skill Inventory; Driving Anger Scale |
| JEL: | R41 |
| Date: | 2015–09–02 |
| URL: | http://d.repec.org/n?u=RePEc:hhs:ctswps:2015_013&r=all |
| By: | DOI Naoshi; OHASHI Hiroshi |
| Abstract: | This paper investigates the economic impacts of the merger between Japan Airlines (JAL) and Japan Air System (JAS) in October 2002 and its remedial measures. This paper performs simulation analyses using an estimated structural model in which airlines set both fares and flight frequencies on each route in the domestic market. By comparing supply models, the hypothesis that the merger caused a collusion among airlines is rejected. The marginal-cost estimates for the merging airlines significantly declined primarily through the expansion of its domestic network. The simulation estimates suggest that, although the merger increased the total social surplus for all domestic routes by 6.8%, it increased fares and decreased consumer surplus on the JAL-JAS duopoly routes. This paper also evaluates remedial measures associated with the merger. |
| Date: | 2015–08 |
| URL: | http://d.repec.org/n?u=RePEc:eti:dpaper:15100&r=all |
| By: | Haahr, J.T.; Wagenaar, J.C.; Veelenturf, L.P.; Kroon, L.G. |
| Abstract: | The assignment of rolling stock units to timetable services in passenger railways is an important optimization problem that has been addressed by many papers in different forms. Solution approaches have been proposed for different planning phases: strategic, tactical, and also operational planning. In this paper we compare two approaches within two operational planning phases (i.e. the daily and the real time planning). The first exact approach is based on a Mixed Integer Linear Program (MILP) which is solved using CPLEX. The second approach is an extension of a recently introduced column generation approach. In this paper, we benchmark the performance of the methods on networks of two countries (Denmark and The Netherlands). We use the approaches to make daily schedules and we test their real time applicability by performing tests with different disruption scenarios. The computational experiments demonstrate that both models can be used on both networks and are able to find optimal rolling stock circulations in the different planning phases. Furthermore, the results show that both approaches are sufficiently fast to be used in a real-time setting. |
| Keywords: | rolling stock units, scheduling, rescheduling, optimization, railway rolling stock, MILP |
| Date: | 2015–06–29 |
| URL: | http://d.repec.org/n?u=RePEc:ems:eureri:78317&r=all |
| By: | Bousonville, Thomas; Ebert, Christian; Rath, Jasmin |
| Abstract: | This paper investigates the impact of different driving behavior evaluation systems on the distribution of monetary rewards for economic driving. It starts with an introduction into truck telematics systems as the most prominent data source for the assessment metrics. Two specific systems are presented in more detail, focusing on the way driver evaluation is performed in each of them. Data that has been collected from the two systems in a real case is used to analyze if the drivers had a fair chance to get the same bonus independently of the system that was built in their truck. |
| Keywords: | telematics,driving behavior,incentives,award systems |
| Date: | 2015 |
| URL: | http://d.repec.org/n?u=RePEc:zbw:htwlog:8&r=all |