It is sometimes claimed that transport infrastructure projects have network effects, which are not taken into account in the appraisal of these projects. This paper reviews the concept of network effects, relates this to transport appraisal practice, and links to the concept of 'total economic...

Remote rural areas tend to experience slower population growth (sometimes decline), slower growth in GDP, fewer employment opportunities and lower productivity relative to the economy as a whole. Transport policy interventions are typically focussed on addressing structural economic weaknesses....

In 1998, the UK Government published the results of its Roads Review. For each of the 68 schemes considered, an Appraisal Summary Table was produced, giving the scheme performance against the Government's five objectives--environment, safety, economy, accessibility and integration. This paper...

It is estimated that on a single night in January 2009, there were 643,067 sheltered and unsheltered homeless people in America (The 2009 Annual Homeless Assessment Report to Congress 2010). The Obama administration recently published “Opening Doors,” the first federal plan to prevent and...

Twenty-one sources of error and bias in the appraisal of transport projects are identified. These relate to objectives, definitions, data, models and evaluation conventions. Objectives may be unclear, incompletely specified or inconsistent with appraisal criteria. Definitions of study areas and...

It has always been a controversial tool, generating accusations of unacceptable principle, improper application, inadequate evidence base and bias. One early application was to the appraisal of the proposed third London Airport where a critic labelled the project appraisal as “nonsense on...