How (In)accurate Are Demand Forecasts in Public Works Projects?: The Case of Transportation

@article{Flyvbjerg2005HowA,
  title={How (In)accurate Are Demand Forecasts in Public Works Projects?: The Case of Transportation},
  author={Bent Flyvbjerg and Mette K. Skamris holm and S{\o}ren L. Buhl},
  journal={Journal of the American Planning Association},
  year={2005},
  volume={71},
  pages={131 - 146}
}
Abstract 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 estimating the demand for transportation infrastructure projects. For 9 out of 10 rail projects, passenger forecasts are overestimated; the… 

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References

SHOWING 1-10 OF 68 REFERENCES

How common and how large are cost overruns in transport infrastructure projects?

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

Cost Underestimation in Public Works Projects: Error or Lie?

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

What Causes Cost Overrun in Transport Infrastructure Projects?

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

THE PERFORMANCE AND IMPACT OF RAIL MASS TRANSIT IN DEVELOPING COUNTRIES

Many Third World cities have recently built metros, usually encouraged by manufacturers and their governments, but frowned on - because of their enormous cost - by many transport planners and aid

THE PREDICTIVE ACCURACY OF BRITISH TRANSPORT STUDIES IN URBAN AREAS

Data from 44 transport studies undertaken in this country between 1962 and 1971 were used to make the first comprehensive assessment of the predictive accuracy of British transport studies by

Underestimating Costs in Public Works Projects: Error or Lie?

Abstract This article presents results from the first statistically significant study of cost escalation in transportation infrastructure projects. Based on a sample of 258 transportation

Forecasting: An Appraisal for Policy-Makers and Planners.

Energy needs...oil supplies...inflation rates...the demand for new homes...in concerns like these, forecasting plays a crucial role. Forecasts not only determine how billions of dollars will be spent

THE COST ESCALATION OF RAIL PROJECTS: USING PREVIOUS EXPERIENCE TO RE-EVALUATE THE CALSPEED ESTIMATES. WORKING PAPER

This report is a follow-up study to last year's CalSpeed publication, "High-Speed Trains for California," Working Paper No. 565. The purpose of this paper is to test rigorously and critically the

Ethics and Advocacy in Forecasting for Public Policy

Forecasting is one of the most important activities performed by professionals in support of public policymaking. In a world dominated by utilitarian thinking, policymakers regularly seek forecasts

World development report 1994 : infrastructure for development

World development report 1994, the seventeenth in this annual series, examines the link between infrastructure and development and explores ways in which developing countries can improve both the
...