Understanding the costs of urban transportation using causal inference methods

With urbanisation on the rise, the need to transport the population within cities in an efficient, safe and sustainable manner has increased tremendously. In serving the growing demand for urban travel, one of the key policy question for decision makers is whether to invest more in road infrastructure or in public transportation. As both of these solutions require substantial spending of public money, understanding their costs continues to be a major area of research. This thesis aims to improve our understanding of the technology underlying costs of operation of public and private modes of urban travel and provide new empirical insights using large-scale datasets and application of causal econometric modelling techniques. The thesis provides empirical and theoretical contributions to three different strands in the transportation literature. Firstly, by assessing the relative costs of a group of twenty-four metro systems across the world over the period 2004 to 2016, this thesis models the cost structure of these metros and quantifies the important external sources of cost-efficiency. The main methodological development is to control for confounding from observed and unobserved characteristics of metro operations by application of dynamic panel data methods. Secondly, the thesis provides a quantification of the travel efficiency arising from increasing the provision of road-based urban travel. A crucial pre-condition of this analysis is a reliable characterisation of the technology describing congestion in a road network. In pursuit of this goal, this study develops novel causal econometric models describing vehicular flow-density relationship, both for a highway section and for an urban network, using large-scale traffic detector data and application of non-parametric instrumental variables estimation. Our model is unique as we control for bias from unobserved confounding, for instance, differences in driving behaviour. As an important intermediate research outcome, this thesis also provides a detailed association of the economic theory underlying the link between the flow-density relationship and the corresponding production function for travel in a highway section and in an urban road network. Finally, the influence of density economies in metros is investigated further using large-scale smart card and train location data from the Mass Transit Railway network in Hong Kong. This thesis delivers novel station-based causal econometric models to understand how passenger congestion delays arise in metro networks at higher passenger densities. The model is aimed at providing metro operators with a tool to predict the likely occurrences of a problem in the network well in advance and materialise appropriate control measures to minimise the impact of delays and improve the overall system reliability. The empirical results from this thesis have important implications for appraisal of transportation investment projects.Open Acces

Matrix recovery using Split Bregman

In this paper we address the problem of recovering a matrix, with inherent low rank structure, from its lower dimensional projections. This problem is frequently encountered in wide range of areas including pattern recognition, wireless sensor networks, control systems, recommender systems, image/video reconstruction etc. Both in theory and practice, the most optimal way to solve the low rank matrix recovery problem is via nuclear norm minimization. In this paper, we propose a Split Bregman algorithm for nuclear norm minimization. The use of Bregman technique improves the convergence speed of our algorithm and gives a higher success rate. Also, the accuracy of reconstruction is much better even for cases where small number of linear measurements are available. Our claim is supported by empirical results obtained using our algorithm and its comparison to other existing methods for matrix recovery. The algorithms are compared on the basis of NMSE, execution time and success rate for varying ranks and sampling ratios

Domestic Sex Trafficking of Aboriginal Girls in Canada: Issues and Implications

The current discourses on human trafficking in Canada do not take into account domestic trafficking, especially of Aboriginal girls. Notwithstanding the alarmingly high number of missing, murdered and sexually exploited Aboriginal girls, the issue continues to be portrayed more as a problem of prostitution than of sexual exploitation or domestic trafficking. The focus of this study is to examine the issues in sexual exploitation of Aboriginal girls, as identified by the grass root agencies, and to contextualize them within the trafficking framework with the purpose of distinguishing sexual exploitation from sex work. In doing so, the paper will outline root causes that make Aboriginal girls vulnerable to domestic trafficking as well as draw implications for policy analysis. Volume 3, Number 3, 2007, pp. 57-71 Questions or correspondence concerning this article may be addressed to

Optimization of Zone Routing Protocol

Reactive and proactive protocols have several advantages in ad hoc network. Proactive protocols provide less delay and reactive protocols uses less bandwidth, but it in order to use these advantages properly, it is better to use them in a combine manner rather than using them independently. A Hybrid protocol takes advantages of these protocols and overcomes the disadvantages of both. A popular hybrid protocol is Zone Routing Protocol. As the name implies the whole network is splitted in different zones. For routing inside the zone proactive protocol is used and between the zones reactive protocol is used. Optimization of ZRP using different radius and nodes on NS2 is executed inside the paper. TORA is used as within the nodes and DSDV between the zones. Performance is judged by using PDR as a parameter. This is done to know at which radius and number of nodes the performance of ZRP is the best. ZRP is a not a distinct protocol as it provide framework for other protocols. KEYWORDS: ZRP, TORA, DSDV, PDR, NS2

Does Citizen–Government Fit Matter? An Exploration in the Context of Online Civic Engagement

Despite technological development and individuals using technologies more than ever, their engagement in e-participation initiatives remains low. A close assessment indicates that simply setting up platforms for e-participation does not inevitably result in online civic engagement. Addressing this gap, this study goes beyond technological factors to consider the citizen-government fit to influence online civic engagement. Using the theoretical lens of person—organization fit, self-efficacy, and the social influence theory, this study argues that (1) the congruence between citizens and their government (i.e., C—G fit) will positively impact online civic engagement and (2) this relationship will be mediated by citizens’ commitment and moderated by e-participation-specific self-efficacy and social networking site usage. Data was collected from six interviews and 14 survey responses as the preliminary study. The data showed an initial indication in support of the research hypotheses. The research method for the final study is described, followed by the implications

Exploratory Study on the Relation between Urban Landscapes and Urban Corridors for Outdoor Thermal Comfort

AbstractUrban Heat Island (UHI) is an increasing phenomenon experienced by most of the growing cites in India. Many researchers have proved that there is a substantial increase in surface temperature between urban and rural areas. The climatic conditions in the man-made urban environment is greatly influenced by roads, buildings and many other factors where the micro-climate of indoor environment can be controlled through various mechanisms whereas the thermal comfort of outdoor environment has very limited control. On the other hand the fundamental role of roads is to move people or goods from one place to another, thereby contributing to the economic development of any city. Roads are inevitable for city planning and are no longer perceived as mere transportation corridor; they can be seen as windows of surroundings and are places that offer high degree of social interaction between people. In the recent years owing to the growth of cities there is tremendous increase in road surface leading to increased UHI effect. This paper through a series of literature study tries to explore the possible relation between urban landscapes and roads towards comfortable outdoor environment. Landscaping is considered to be one of the effective means of passive cooling