Mette K Skamris

This article presents results from the first statistically significant study of cost escalation in transportation infrastructure projects. Based on a sample of 258 transportation infrastructure projects worth $90 billion (U.S.), it is found with overwhelming statistical significance that the cost estimates used to decide whether important infrastru...

Results from the first statistically significant study of the causes of cost escalation in transport infrastructure projects are presented. The study is based on a sample of 258 rail, bridge, tunnel and road projects worth US$90 billion. The focus is on the dependence of cost escalation on (1) length of project implementation phase, (2) size of pro...

This article presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth US$59 billion. The study shows with very high statistical significance that forecasters generally do a poor job of estimati...

This article presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth US$59 billion. The study shows with very high statistical significance that forecasters generally do a poor job of estimati...

This paper presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth US$58 billion. The study shows with very high statistical significance that forecasters generally do a poor job of estimating...

The Summer 2005 issue of JAPA contains a letter from the President of the American Public Transportation Association, William Millar, regarding our article “How (In)accurate Are Demand Forecasts in Public Works Projects? The Case of Transportation,” printed in the Spring issue. We concluded that transit ridership forecasts are frequently and highly...

This article presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth U.S.$59 billion. The study shows with very high statistical significance that forecasters generally do a poor job of estima...

Esistono pochi studi comparati sui costi reali e i costi stimati per la realizzazione di infrastrutture di trasporto e quelli a disposizione riguardano generalmente casi singoli o un campione di progetti troppo limitato per consentire un’analisi statistica sistematica. Per quanto ci risulta, c’è un solo studio che, prendendo in esame 66 progetti di...

Results from the first statistically significant study of the causes of cost escalation in transport infrastructure projects are presented. The study is based on a sample of 258 rail, bridge, tunnel and road projects worth US$90 billion. The focus is on the dependence of cost escalation on: (1) the length of the project‐implementation phase, (2) th...

I den här artikeln presenterar vi resultat från den första statistiskt säkerställda studien av kostnadsökningar i infrastrukturprojekt. Datainsamlingen pågick under fyra år och omfattar ett stort antal infrastrukturprojekt som slutförts mellan 1928 och 1998. Sammanlagt analyserade vi 258 projekt i 20 länder i 5 världsdelar, en projektportfölj värd...

Es gibt nur wenige vergleichende Studien über reale und geschätzte Kosten derEntwicklung von Verkehrsinfrastruktur. Wo solche Studien vorliegen, beziehen siesich auf Einzelfälle, oder die Stichprobe ist zu klein, um systematische statistische Analysen zuzulassen (Bruzelius et al. 1998, Fouracre et al. 1990, Hall 1980, Nijkamp/Ubbels 1999, Pickrell...

The autumn 2002 issue of JAPA contains a letter from Roger Remington that expands in a useful manner on our article “Underestimating Costs in Public Works Projects: Error or Lie?” published in the summer 2002 issue. We agree with and welcome most of what Remington writes, including that the headline in the (London) Sunday Times (July 7, 2002) stati...

Despite the hundreds of billions of dollars being spent on infrastructure development -- from roads, rail and airports to energy extraction and power networks to the Internet -- surprisingly little reliable knowledge exists about the performance of these investments in terms of actual costs, benefits and risks. This paper presents results from the...

This article presents results from the first statistically significant study of cost escalation in transportation infrastructure projects. Based on a sample of 258 transportation infrastructure projects worth US$90 billion and representing different project types, geographical regions, and historical periods, it is found with overwhelming statistic...

Little research has been carried out on before-and-after studies of traffic and costs in large transport infrastructure projects. The few studies made all show a tendency for forecasts of construction costs to be underestimated, and for traffic forecasts to be overestimated. An examination of construction costs and traffic in seven large Danish bri...

Little research has been carried out on before-and-after studies of traffic and construction costs in large transportation infrastructure projects. The few studies that do exist show that forecasts of construction costs tend to be underestimated and those of traffic, overestimated. An examination of construction costs and traffic in seven large Dan...

Little research has been carried out on before-and-after studies of traffic and construction costs in large transportation infrastructure projects. The few studies that do exist show that forecasts of construction costs tend to be underestimated and those of traffic, overestimated. An examination of construction costs and traffic in seven large Dan...

ZUSAMMENFASSUNG In der vorliegenden Arbeit werden die Resultate der ersten statistisch relevanten Studie über die Ursachen der Kostenüberschreitung bei Verkehrsinfrastrukturprojekten vorgestellt. Der Studie liegt eine Stichprobe von 258 Schienen-, Brücken-, Tunnel-und Straßenbauprojekten mit einem Volumen von 90 Milliarden US-Dollar zugrunde. Der S...