A note on the use of correlation coefficients for assessing goodness-of-fit in spatial interaction models

The use of correlation coefficients to evaluate the accuracy of spatial interaction models is inappropriate unless such models have been fitted using least squares techniques. In other cases the correlation involves an implicit intercept value and a regression coefficient that may significantly modify the interaction model's estimates. Researchers have not acknowledged the role of these two parameters when the correlation is used. A generalized root mean square error is proposed as an alternative indicator of accuracy that may be used with any model.     

如何建立自己的维修资料库

当今的汽车维修资料和信息有各种载体,将这些所有的载体都组织得井井有条并方便使用需要决心,一旦下了决心,就会有很大的回报。 也许你还没注意到,能有效地维修和保养当今的车辆所需要的信息量已成指数级地增长。要修好一辆车得需要维     

Techniques of land use/transportation planning in Australian cities

With the publication of the Sydney Area Transportation Study, land-use/transportation studies now have been conducted in all capital cities as well as in the majority of other urban areas with populations in excess of 40.000. A review of these studies is made and a qualitative assessment is attempted of the technical phases —land-use planning, trip-generation, trip-distribution, modal-split, traffic assignment and evaluation. Full summary results of this comparative survey are presented in tabular form, although themes developed in the text are illustrated with specific examples from individual studies. The methodology of land-use/transportation studies has been attacked by some Australian writers. An attempt is made to assess the relevance of these criticisms when applied to the practical planning process in Australia.     

2000年悉尼奥运会的战略交通规划、交通基础设施的需求分析和交通服务

本文给出了一个简要的交通战略规划、总体规划和操作规划的描述。战略规划必须发生在政策容许范围内。就城市交通而言，交通的可持速发展非常重要，本文给出了来自悉尼的一些例子。通过2000年悉尼奥林匹克运动会的案例研究解释了交通的需求分析。本文还为北京奥林匹克运动会的交通战略规划进程提出了建议。     

An object-oriented approach to transport modelling: Software development to calculate road traffic noise

A framework for developing object-oriented software in transport modelling in proposed and demonstrated with the implementation of the calculation of road traffic noise (CORTN). Major tasks in the life cycle of an object-oriented development process are identified, and illustrated with the implementation of TRANSOOP – a software library containing 33,000 lines of C++ programming code. Software re-use from this library to produce a object-oriented noise program is compared with conventional computer programming shows that almost 90 per cent of the lines of code were drawn from TRANSOOP. Advantages of the object-oriented approach are discussed.     

An analysis of gravity model distance exponents

This study examines variations in the basic parameter of the gravity model: the distance or travel time exponent. In a conceptual examination of the exponent under ideal conditions, it is noted that the exponent will be low if either production or consumption of the phenomena is geographically concentrated. It is further noted that if all regions produce and consume the phenomena, this generally implies a large number of substitute regions, and therefore a large exponent. These three variables are made operational and related to a set of eighty exponents for 1967 commodity flows in the United States. A multiple regression model is derived and utilized to estimate the exponents. The latter are then used to reestimate the flows. The root mean squared errors are quite similar for the fitted and estimated exponents. Implications of the research appear to be consistent with variations of the exponent in the urban context.     

A critical examination of an airport noise mitigation scheme and an aircraft noise charge: the case of capacity expansion and externalities at Sydney (Kingsford Smith) airport

In the wake of the Australian airline liberalization in 1990 and its forecasted impact on air traffic, capacity has been expanded at Sydney (Kingsford Smith) airport (Sydney KSA) – Australia's busiest commercial airport – with the construction of the third runway in 1994. Coinciding with the approval for this capacity expansion, the Commonwealth Government amended the Federal Airports Corporation (FAC) Act to direct the FAC to carry out activities which protect the environment from the effects of aircraft operations, with the cost to be borne by the airline industry according to the ‘Polluter Pays Principle'. Noise management plans were part of the conditions for developmental approval for a third runway. To this end, since 1995, Sydney KSA imposes a noise levy designed to generate sufficient revenues to fund a noise mitigation scheme. Although the issues of aircraft noise, in particular its impact on property values and land use planning around the airport, have been extensively addressed in the literature, no one has empirically examined the implications of new environmental policies in conjunction with airline liberalization and change in airport infrastructure. Principles and policy analyses are discussed in this paper. By focusing on the specifics of Sydney KSA, broader policy issues likely to be relevant for other major airports around the world are discussed.