1,564 research outputs found

    Optimization of headway, stops, and time points considering stochastic bus arrivals

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    With the capability to transport a large number of passengers, public transit acts as an important role in congestion reduction and energy conservation. However, the quality of transit service, in terms of accessibility and reliability, significantly affects model choices of transit users. Unreliable service will cause extra wait time to passengers because of headway irregularity at stops, as well as extra recovery time built into schedule and additional cost to operators because of ineffective utilization of allocated resources. This study aims to optimize service planning and improve reliability for a fixed bus route, yielding maximum operator’s profit. Three models are developed to deal with different systems. Model I focuses on a feeder transit route with many-to-one demand patterns, which serves to prove the concept that headway variance has a significant influence on the operator profit and optimal stop/headway configuration. It optimizes stop spacing and headway for maximum operator’s profit under the consideration of demand elasticity. With a discrete modelling approach, Model II optimizes actual stop locations and dispatching headway for a conventional transit route with many-to-many demand patterns. It is applied for maximizing operator profit and improving service reliability considering elasticity of demand with respect to travel time. In the second model, the headway variance is formulated to take into account the interrelationship of link travel time variation and demand fluctuation over space and time. Model III is developed to optimize the number and locations of time points with a headway-based vehicle controlling approach. It integrates a simulation model and an optimization model with two objectives - minimizing average user cost and minimizing average operator cost. With the optimal result generated by Model II, the final model further enhances system performance in terms of headway regularity. Three case studies are conducted to test the applicability of the developed models in a real world bus route, whose demand distribution is adjusted to fit the data needs for each model. It is found that ignoring the impact of headway variance in service planning optimization leads to poor decision making (i.e., not cost-effective). The results show that the optimized headway and stops effectively improve operator’s profit and elevate system level of service in terms of reduced headway coefficient of variation at stops. Moreover, the developed models are flexible for both planning of a new bus route and modifying an existing bus route for better performance

    Environmental Law and Policy

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    This chapter provides an economic perspective of environmental law and policy with regard to both normative and positive dimensions. It begins with an examination of the central problem in environmental regulation: the tendency of pollution generators in an unconstrained market economy to externalize some of the costs of their production, leading to an inefficiently large amount of pollution. We examine the ends of environmental policy, that is, the setting of goals and targets, beginning with normative issues, notably the Kaldor-Hicks criterion and the related method of assessment known as benefit-cost analysis. We examine this analytical method in detail, including its theoretical foundations and empirical methods of estimation of compliance costs and environmental benefits. We include a review of critiques of benefit-cost analysis, briefly examine alternative approaches to analyzing the goals of environmental policies, and survey the efforts of the Federal governmental to employ these analytical methods. The chapter also examines in detail the means of environmental policy, that is, the choice of specific policy instruments, beginning with an examination of potential criteria for assessing alternative instruments, with particular focus on cost-effectiveness. The theoretical foundations and experiential highlights of individual instruments are reviewed, including conventional, command-and-control mechanisms, economic incentive or market-based instruments, and liability rules. In the economic-incentive category, we consider pollution charges, tradeable permit systems, market friction reductions, and government subsidy reductions. Three cross-cutting issues receive attention: implications of uncertainty for instrument choice; effects of instrument choice on technological change; and distributional considerations. We identify a set of normative lessons in regard to design, implementation, and the identification of new applications, and we examine positive issues, including three phenomena: the historical dominance of command-and-control; the prevalence in new proposals of tradeable permits allocated without charge; and the relatively recent increase in attention given to market-based instruments. Finally, the chapter turns to the question of how environmental responsibility is and should be allocated among the various levels of government. We provide a positive review of the responsibilities of Federal, state, and local levels of government in the environmental realm, plus a normative assessment of this allocation of regulatory responsibility. We focus on three arguments that have been made for Federal environmental regulation: competition among political jurisdictions and the race to the bottom; transboundary environmental problems; and public choice and systematic bias.

    Environmental Law and Public Policy

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    This chapter provides an economic perspective of environmental law and policy with regard to both normative and positive dimensions. It begins with an examination of the central problem in environmental regulation: the tendency of pollution generators in an unconstrained market economy to externalize some of the costs of their production, leading to an inefficiently large amount of pollution. We examine the ends of environmental policy, that is, the setting of goals and targets, beginning with normative issues, notably the Kaldor-Hicks criterion and the related method of assessment known as benefit-cost analysis. We examine this analytical method in detail, including its theoretical foundations and empirical methods of estimation of compliance costs and environmental benefits. We include a review of critiques of benefit-cost analysis, briefly examine alternative approaches to analyzing the goals of environmental policies, and survey the efforts of the Federal governmental to employ these analytical methods. The chapter also examines in detail the means of environmental policy, that is, the choice of specific policy instruments, beginning with an examination of potential criteria for assessing alternative instruments, with particular focus on cost-effectiveness. The theoretical foundations and experiential highlights of individual instruments are reviewed, including conventional, commandand- control mechanisms, economic incentive or market-based instruments, and liability rules. In the economic-incentive category, we consider pollution charges, tradeable permit systems, market friction reductions, and government subsidy reductions. Three cross-cutting issues receive attention: implications of uncertainty for instrument choice; effects of instrument choice on technological change; and distributional considerations. We identify a set of normative lessons in regard to design, implementation, and the identification of new applications, and we examine positive issues, including three phenomena: the historical dominance of command-and-control; the prevalence in new proposals of tradeable permits allocated without charge; and the relatively recent increase in attention given to market-based instruments. Finally, the chapter turns to the question of how environmental responsibility is and should be allocated among the various levels of government. We provide a positive review of the responsibilities of Federal, state, and local levels of government in the environmental realm, plus a normative assessment of this allocation of regulatory responsibility. We focus on three arguments that have been made for Federal environmental regulation: competition among political jurisdictions and the race to the bottom; transboundary environmental problems; and public choice and systematic bias.environmental economics, environmental law, efficiency, cost-effectiveness, benefitcost analysis, environmental federalism

    Environmental Law and Policy

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    This chapter for the Handbook of Law and Economics provides an economic perspective of environmental law and policy. We examine the ends of environmental policy, that is, the setting of goals and targets, beginning with normative issues, notably the Kaldor-Hicks criterion and the related method of assessment known as benefit-cost analysis. We examine this analytical method in detail, including its theoretical foundations and empirical methods of estimation of compliance costs and environmental benefits. We review critiques of benefit-cost analysis, and examine alternative approaches to analyzing the goals of environmental policies. We examine the means of environmental policy, that is, the choice of specific policy instruments, beginning with an examination of potential criteria for assessing alternative instruments, with particular focus on cost-effectiveness. The theoretical foundations and experiential highlights of individual instruments are reviewed, including conventional, command-and-control mechanisms, market-based instruments, and liability rules. Three cross-cutting issues receive attention: uncertainty; technological change; and distributional considerations. We identify normative lessons in regard to design, implementation, and the identification of new applications, and we examine positive issues: the historical dominance of command-and-control; the prevalence in new proposals of tradeable permits allocated without charge; and the relatively recent increase in attention given to market-based instruments. We also examine the question of how environmental responsibility is and should be allocated among the various levels of government. We provide a positive review of the responsibilities of Federal, state, and local levels of government in the environmental realm, plus a normative assessment of this allocation of regulatory responsibility. We focus on three arguments that have been made for Federal environmental regulation: competition among political jurisdictions and the race to the bottom; transboundary environmental problems; and public choice and systematic bias.

    Managerial decisions to recover from Covid-19 disruption: A multi-objective optimization approach applied to public transport operators

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    The resilience of transport systems, facing natural or man-made disruptions, has been widely discussed in literature in terms of recovery capabilities concerning infrastructures, suggesting solutions to provide users an acceptable level of service along the interrupted network. However, in the context of the Covid-19 outbreak, the disruption has stressed the resilience of transport systems not on the supply side but rather at organizational level for transport service providers. Indeed, the sudden and drastic decrease in users due to the restrictions imposed by governments to limit the pandemic spread has implicated severe economic consequences in the running of transport companies. In this paper, attention has been focused on the public transport sector to analyse the effects of different initiatives, which companies could undertake in response to the demand shock caused by the Covid-19 emergency. Notably, an optimization procedure has been developed with the aim of determining feasible Pareto-front solutions, which correspond to trade-off conditions for the concurrent maximization of the company profit and the minimization of outsourcing services. The time span necessary to implement the examined recovery measures has been considered together with the limitation to appropriate threshold values for the main cost and income items influencing the company operations management. The proposed approach has been applied to the case study of an Italian public transport company to appraise different post-Covid-19 resilience strategies

    THE PUBLIC TRANSIT SYSTEMS IN ITALY: A CRITICAL ANALYSIS OF THE REGULATORY FRAMEWORK

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    In this paper we attempt to shed some light on the way the regulation of public transit systems has been approached in the past and is presently addressed in Italy. The reduction of x-inefficiency represents a great challenge for the local authorities, given the high operating costs faced by the transportation companies and the moderate tariffs level that do not allow the operators to balance costs and revenues. Throughout the 1980’s and the first half of the 1990’s, the problem was essentially met by means of stopgap measures taken mainly for emergency, to curb the deficit build-up. In the past five years it has been turning the efforts towards a radical reorganization of the whole local public transportation (LPT) industry, with the law 549/95, completed with the Decreti Legge 422/97 and 400/99. The reform process includes among its goals the attribution of financial responsibility to the sector operators and the start of privatization of the public transit systems. The introduction of more competitive environment, mainly by the resort to tendering for the allotment of concessions, represents the challenge for the future. A complete evaluation of the achieved results is probably still premature. Nevertheless, as the first goal is concerned, the reform appears suitable to yield some positive result. On the contrary, the liberalization and privatization of the LPT sector is progressing very slowly, due to the protection still given to the public-owned companies. It is then expected that in the future a decisive action with regard to such important aspects of the regulatory reform will be undertaken.

    Planning for Excellence: Insights from an International Review of Regulators’ Strategic Plans

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    What constitutes regulatory excellence? Answering this question is an indispensable first step for any public regulatory agency that is measuring, striving towards, and, ultimately, achieving excellence. One useful way to answer this question would be to draw on the broader literature on regulatory design, enforcement, and management. But, perhaps a more authentic way would be to look at how regulators themselves define excellence. However, we actually know remarkably little about how the regulatory officials who are immersed in the task of regulation conceive of their own success. In this Article, we investigate regulators’ definitions of regulatory excellence by drawing on a unique source of data that provides an important window on regulators’ own aspirations: their strategic plans. Strategic plans have been required or voluntarily undertaken for the past decade or longer by regulators around the globe. In these plans, regulators offer mission statements, strategic goals, and measurable and achievable outcomes, all of which indicate what regulators value and are striving to become. Occasionally, they even state explicitly where they have fallen short of “best-in-class” status and how they intend to improve. To date, a voluminous literature exists examining agency practices in strategic planning, but we are aware of no study that tries to glean from the substance of a sizeable number of plans how regulators themselves construe regulatory excellence. The main task of this Article is undertaking this effort. This Article draws on twenty plans from different regulators in nine countries. We found most generally that excellent regulators describe themselves (though not necessarily using exactly these words) as institutions that are more (1) efficient, (2) educative, (3) multiplicative, (4) proportional, (5) vital, (6) just, and (7) honest. In addition to these seven shared attribute categories, our reading of the plans also revealed five other “unusual” attributes that only one or two agencies mentioned. Beyond merely cataloguing the attributes identified by agencies, this Article also discusses commonalities (and differences) between plan structures, emphases, and framings. We found that the plans differed widely in features such as the specificity of their mission statements, the extent to which they emphasized actions over outcomes (or vice versa), and the extent to which commitments were organized along organizational fiefdoms or cut across bureaucratic lines. We urge future scholarship to explore alternative methods of text mining, and to study strategic plans over time within agencies, in order to track how agencies’ notions of regulatory excellence respond to changes in the regulatory context and the larger circumstances within which agencies operate. Looking longitudinally will also shed light on how agencies handle strategic goals that are either met or that prove to be unattainable

    Cutting the Climate-Development Gordian Knot - Economic options in a politically constrained world

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    Combating climate change cannot but be a cooperative venture amongst nations. Together with the problem posed by the withdrawal of the US from the Kyoto Protocol, the key challenge for winning the battle is the involvement of developing countries in efforts to alter their GHGs emissions trends. This involvement is necessary technically but also politically to bring the largest emitter of the planet back on the battle field. In the first section we draw on history to outline the intellectual underpinning of North/South divide around climate affairs. In the second section we show the economic basis for a leverage effect between development and climate policies. The third section ventures to propose some guidance to develop a viable climate regime strong enough to support an ambitious effort to decarbonize economies and we show that the Kyoto framework, once re-interpreted and amended is not so far from this working drawing.climate policy; development
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