How Can We Improve Evaluation Methods for Public Infrastructure?
Abstract
Given the smaller total budget for public expenditure and the fact that the cost of public funds to Ireland has increased, it is more important than ever to ensure that public investment is prioritised properly in order to derive maximum benefit. Inorder to prioritise we must evaluate. A variety of evaluation methods can be utilised, but perhaps the most widely used is cost benefit analysis. The usefulness of costbenefit analysis crucially depends on a number of parameters and inputs. This paper considers the international literature on two issues, namely, the impact of risk in theform of inaccurate cost or benefit estimates and the setting of the appropriate discount rate, both of which can impact significantly on the usefulness of costbenefit analysis. The evidence on the expected costs and benefits of projects highlights that projects often do not go according to plan and that these estimates are subject to systematic optimism bias, which, while not universal, appears to be widespread. In relation to the appropriate choice of a discount rate, a riskless rate should in general not be used unless all risks have been properly assessed and costed within the analysis. This paper concludes that the discount rates that are currently used in Ireland appear to be low. Furthermore, the paper highlights that if the conventional exponential discounting is used then costs and benefits that occur in the distant future are essentially ignored. A declining discount rate accounts better for costs/benefits that occur in the distant future and is consistent with the observed pattern of time preference of individuals. This paper recommends a hybrid approach be adopted where costs and benefits are discounted using exponential discounting up to a point at which the discounting is switched to declining discounting.Download Info
If you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.Bibliographic Info
Paper provided by Economic and Social Research Institute (ESRI) in its series Papers with number EC2.Length:
Date of creation: Nov 2011
Date of revision:
Handle: RePEc:esr:wpaper:ec2
Contact details of provider:
Postal: Whitaker Square, Sir John Rogerson's Quay, Dublin 2
Phone: (353-1) 863 2000
Fax: (353-1) 863 2100
Email:
Web page: http://www.esri.ie
More information through EDIRC
Related research
Keywords:This paper has been announced in the following NEP Reports:
- NEP-ALL-2012-02-27 (All new papers)
- NEP-PPM-2012-02-27 (Project, Program & Portfolio Management)
References
References listed on IDEASPlease report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- John Bradley & Timo Mitze & Edgar Morgenroth & Gerhard Untiedt, 2006. "How can we know if EU cohesion policy is successful? Integrating micro and macro approaches to the evaluation of Structural Funds," Working Papers 1-2006, GEFRA - Gesellschaft fuer Finanz- und Regionalanalysen.
- Martin L. Weitzman, 2009.
"Risk-Adjusted Gamma Discounting,"
NBER Working Papers
15588, National Bureau of Economic Research, Inc.
- Weitzman, Martin L., 2010. "Risk-adjusted gamma discounting," Journal of Environmental Economics and Management, Elsevier, vol. 60(1), pages 1-13, July.
Citations
Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.Cited by:
- Driscoll, Áine & Lyons, Seán & Mariuzzo, Franco & Tol, Richard S. J., 2012. "Simulating Demand for Electrical Vehicles using Revealed Preference Data," Papers WP437, Economic and Social Research Institute (ESRI).
Lists
This item is not listed on Wikipedia, on a reading list or among the top items on IDEAS.Statistics
Access and download statisticsCorrections
When requesting a correction, please mention this item's handle: RePEc:esr:wpaper:ec2For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Sarah Burns).
If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.
If references are entirely missing, you can add them using this form.
If the full references list an item that is present in RePEc, but the system did not link to it, you can help with this form.
If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your profile, as there may be some citations waiting for confirmation.
Please note that corrections may take a couple of weeks to filter through the various RePEc services.

