conference paper
published journal article
published journal article
published journal article
Cities worldwide are facing new challenges and opportunities with the proliferation of Unmanned Aerial Vehicles (UAVs), or drones. However, despite the increasing importance of managing drone activities at the local level, little is known about the extent to which cities adopt regulatory measures to deal with the challenges posed by this emerging technology and the factors that determine the local policy adopted. This study examines the dynamics of local drone policy adoption, focusing on California, which has the largest population of drones currently registered in the United States. A review of 482 California cities’ municipal codes shows evolving patterns of policy adoption over the last two decades, with a rapid expansion since 2015. Multivariate survival analysis indicates that policy adoption at the local level is shaped by both municipal capacity and motivation factors, including the actions of neighboring cities. The analysis also finds evidence of disparities associated with socio-demographics, calling for more attention to the variation in local policy responsiveness to technology-driven challenges and ways to support local efforts and their collaboration.
research report
working paper
Many previous studies of transport tax reform have explicitly or implicitly assumed that the reform itself does not affect the marginal value of time. In this paper we consider a simple model with multiple trip purposes, commuting and non-commuting transport, to analyse the implications of transport tax reform for the value of time and for marginal external congestion costs. The theoretical analysis shows that transport taxes may both increase or reduce the value of time and it identifies the conditions under which either outcome will occur. The results further suggest that if a tax reform in the transport sector is accompanied by labour tax adjustments to reduce the distortionary cost of the tax system, the marginal value of time will typically increase. The implications of endogenous values of time for models of optimal externality taxes and studies of tax reform in the transport sector are empirically illustrated using a numerical model, calibrated using Belgian data. It is found that the impact of tax changes on the value of time is non-trivial. Moreover, many of the tax reform exercises considered simultaneously reduce traffic levels but raise marginal external congestion costs. The results of this paper suggest that incorrectly assuming exogenous time values may strongly bias optimal congestion taxes and lead to misleading welfare effects of transport tax reform.
conference paper
In this era of heightened competition many firms have turned to supply chain partners to collaborate to alleviate their operational inefficiencies and cut costs. Supply chain relationships are transforming to collaborative ventures, sometimes even with their competitors. In this paper we study the issues facing an electronic intermediary or a third party logistics company for achieving collaboration for transportation demands from a group of small to medium sized shippers in an Internet marketplace. We develop a methodology for studying the shipper collaboration problems and provide formulations for partly loaded and truckload shipments. The underlying cost allocation issues facing the collaborations are examined from a cooperative game theory perspective. We point out that finding stable cost allocation mechanisms are NP-Hard and develop simple heuristic cost allocation mechanisms.
published journal article
published journal article
working paper
Any uniform set of transit performance indicators must be constructed with due regard to both their intended use, and to the limitations of available data. This paper presents and applies nine possible performance indicators which might be used for annual, comparative evaluation of transit system performance. The nine indicators comprising this set rely, with one exception, on generally available operating and financial data; they are able to reflect changes in system management and policy and they minimize the effects of differing operating environments. While minimized in their effect, environmental factors must be included in the case studies used to illustrate the application of the performance indicators.