Es gibt nur wenige vergleichende Studien uber reale und geschatzte Kosten derEntwicklung von Verkehrsinfrastruktur. Wo solche Studien vorliegen, beziehen siesich auf Einzelfalle, 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 1990, Skamris/Flyvbjerg 1997, Szyliowicz/Goetz 1995, Walmsley/Pickett 1992). Nach unserem Kenntnisstand ist bislang nur eine Studie veroffentlicht, die auf der Basis von 66 Transportprojekten einen breit angelegtenZugang wahlt und erste Schritte auf dem Weg zu einer stichhaltigen statistischen Analyse unternimmt (Merewitz 1973a, 1973b).Existing comparative studies of actual and estimated costs in transportation infrastructure development are few. Where such studies exist, they are typically single-case studies or they cover a sample of projects too small to allow systematic, statistical analyses (Bruzelius et al., 1998; Fouracre et al., 1990; Hall, 1980; Nijkamp & Ubbels, 1999; Pickrell, 1990; Skamris & Flyvbjerg, 1997; Szyliowicz & Goetz, 1995; Walmsley & Pickett, 1992). To our knowledge, only one study exists that, with a sample of 66 transportation projects, approaches a large-sample study and takes a first step toward valid statistical analysis (Merewitz, 1973a, 1973b).The English version of this article can be found at: http://www.ssrn.com/abstract=2278415Den Svenska versionen av denna artikel finns pa: http://papers.ssrn.com/abstract=2278382La versione italiana di questo documento e disponibile al seguente link: http://www.ssrn.com/abstract=2278294

https://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID2278383_code1935014.pdf?abstractid=2278383

Kostenunterschätzung bei öffentlichen bauprojekten: fehler oder lüge? (Underestimating Costs 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 projects worth US$90 billion and representing different project types, geographical regions, and historical periods, it is found with overwhelming statistical significance that the cost estimates used to decide whether such projects should be built are highly and systematically misleading. Underestimation cannot be explained by error and is best explained by strategic misrepresentation, that is, lying. The policy implications are clear: legislators, administrators, investors, media representatives, and members of the public who value honest numbers should not trust cost estimates and cost-benefit analyses produced by project promoters and their analysts.

/pdf/underestimating-costs-in-public-works-projects-error-or-lie-1ebe1nafmv.pdf

Underestimating Costs in Public Works Projects: Error or Lie?

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

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 estimating the demand for transportation infrastructure projects. For 9 out of 10 rail projects, passenger forecasts are overestimated; the average overestimation is 106%. For half of all road projects, the difference between actual and forecasted traffic is more than ±20%. The result is substantial financial risks, which are typically ignored or downplayed by planners and decision makers to the detriment of social and economic welfare. The data also show that forecasts have not become more accurate over the 30-year period studied, despite claims to the contrary by forecasters. The causes of inaccuracy in forecasts are different for rail and road projects, with deliberately slanted forecasts playing a larger role for rail than for road. The cure is transparency, accountability, and new forecasting methods. The challenge is to change the governance structures for forecasting and project development. The article shows how planners may help achieve this.Listed as "Most Cited" article on the journal's home page.

https://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID2238050_code1935014.pdf?abstractid=2238050&mirid=1&type=2

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

Foreword 1. The Nature of Partnerships 2. The Revolution in Infrastructure 3. The Origins of Partnerships 4. Partnerships and Conventional Procurement of Infrastructure 5. The Structure of Partnership Agreements 6. Issues in Public Private Partnerships 7. Risk Management 8. The Governance of Partnerships 9. PPPs in Emerging Markets 10. An Assessment References Index.

Public Private Partnerships: The Worldwide Revolution In Infrastructure Provision And Project Finance

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 agencies. How have these metros performed? Were they justified in either financial or economic terms? Should more cities be planning to do likewise, or are metros really a luxury that poor cities should forgo? With urban growth and traffic congestion continuing unabated in much of the Third World, it is important to understand the conflicting claims for and against metro investment. This Report presents the findings of a world-wide study involving observations and data collected in 21 developing cities, and the analysis of that data using a strategic transport evaluation model. It explores the hopes expressed for metros, and the reality - particularly the common misconception that they will 'cure' traffic congestion. The Report concludes that while there is much to praise in the engineering and operation of Third World metros, much criticism can justifiably be levelled at their planning and financial management. Few, if any, of them can be financially viable, but can give good economic returns in the right conditions. The study has produced a checklist of guidelines on these conditions which, although far from universal rules, provide a useful first screening on the likely success of a particular metro investment.

The performance and impact of rail mass transit in developing countries

The work described in this report was carried out by a study team from Halcrow Fox and Associates and the Overseas Unit of the Transport and Road Research Laboratory (TRRL), to examine under what conditions, mass transit rail systems could be justified in developing countries, and also to consider how aid agencies could appraise such projects. Field work consisted of visits to 21 selected cities and collecting information. The cities included 9 with established metros (Hong Kong, Manila, mexico City, Porto Alegre, Pusan, Rio de Janeiro, Santiago, Sao Paulo, and Seoul), 4 with incomplete but recently opened metros (Cairo, Calcutta, Singapore and Tunis) two with metros under construction (Istanbul and Medellin) and six with plans for metros (Bogota,Bombay,Dehli, Jakarta,Karachi and Kuala Lumpar). Standard model procedures were utilized to produce a strategic model designed to require relatively little data. The model comprised a traffic (and land use) model and separate evaluation model. On average 62% of the gross benefits predicted from the Metros in the evaluation year were time savings, and these benefits were largely enjoyed by former bus passengers. The study confirms that Metros are not generally financially viable in developing countires. The conditions necessary to bring economic viability to a project relate to corridor and city size, higher than average per capita growth, and growth prospects, efficient administration of the metro system, and financial support for fares. Finally, implications for aid agencies are discussed. It is thought unlikely that aid agencies will support metro projects which have less than 10% to 12% econmic rate of return.

Study of mass rapid transit in developing countries

The Overseas Development Administration (ODA) has sponsored a research study to examine the following topics: (1) financial and economic review of metros; (2) project appraisal; and (3) project costs. This paper summarises the findings. The Study Team went to 21 developing cities and collected data which was analysed on a strategic transport evaluation model. They enquired into the reasons why people wanted metros and noted a widespread misconception that the metro would cure traffic congestion. The Study found much to praise in the engineering and operation of the Third World metros, but much to criticise in their planning and financial management. It concluded that metros - in developing cities at least - cannot be financially viable but can give good economic returns in the right conditions, which it endeavoured to spell out in broad terms. The Study noted the strong connection between the metro and the growth of the city centre; it concluded that very large cities must either build metros or see the growth of their centres frustrated by inaccessibility, with corresponding growth diverted to suburban centres. (Author/TRRL)

Rail mass transit in developing cities - the transport and road research laboratory study . rail mass systems for developing countries. proceedings of the conference organised by the institution of civil engineers, london, october 9-10, 1989

J M Thomson

Papers

The performance and impact of rail mass transit in developing countries

Study of mass rapid transit in developing countries

Rail mass transit in developing cities - the transport and road research laboratory study . rail mass systems for developing countries. proceedings of the conference organised by the institution of civil engineers, london, october 9-10, 1989