On the optimality of expert-adjusted forecasts
Official forecasts of international institutions are never purely model-based. Preliminary results of models are adjusted with expert opinions. What is the impact of these adjustments for the forecasts? Are they necessary to get 'optimal' forecasts? When model-based forecasts are adjusted by experts, the loss function of these forecasts is not a mean squared error loss function. In fact, the overall loss function is unknown. To examine the quality of these forecasts, one can rely on the tests for forecast optimality under unknown loss function as developed in Patton and Timmermann (2007). We apply one of these tests to ten variables for which we have model-based forecasts and expert-adjusted forecasts, all generated by the Netherlands Bureau for Economic Policy Analysis (CPB). For almost all variables the added expertise yields better forecasts in terms of fit. In terms of optimality, the effect of adjustments for the forecasts is limited, because for most variables the assumption that the forecast are not optimal can be rejected for both the model-based and the expert-adjusted forecasts.
|Date of creation:||Dec 2007|
|Date of revision:|
|Contact details of provider:|| Postal: Postbus 80510, 2508 GM Den Haag|
Phone: (070) 338 33 80
Fax: (070) 338 33 50
Web page: http://www.cpb.nl/
More information through EDIRC
Please 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.:
- Clements, Michael P, 1995. "Rationality and the Role of Judgement in Macroeconomic Forecasting," Economic Journal, Royal Economic Society, vol. 105(429), pages 410-20, March.
- Henk Kranendonk & Johan Verbruggen, 2007. "SAFFIER; a multi-purpose model of the Dutch economy for short-term and medium-term analyses," CPB Document 144, CPB Netherlands Bureau for Economic Policy Analysis.
- William D. Nordhaus, 1985.
"Forecasting Efficiency: Concepts and Applications,"
Cowles Foundation Discussion Papers
774, Cowles Foundation for Research in Economics, Yale University.
- Henk Don & Johan Verbruggen, 2006.
"Models and methods for economic policy; 60 years of evolution at CPB,"
CPB Discussion Paper
55, CPB Netherlands Bureau for Economic Policy Analysis.
- F. J. H. Don & J. P. Verbruggen, 2006. "Models and methods for economic policy: 60 years of evolution at CPB," Statistica Neerlandica, Netherlands Society for Statistics and Operations Research, vol. 60(2), pages 145-170.
- Patton, Andrew J. & Timmermann, Allan, 2007. "Testing Forecast Optimality Under Unknown Loss," Journal of the American Statistical Association, American Statistical Association, vol. 102, pages 1172-1184, December.
- Clements,Michael & Hendry,David, 1998.
"Forecasting Economic Time Series,"
Cambridge University Press, number 9780521632423, june. pag.
- Christoffersen, Peter F, 1998. "Evaluating Interval Forecasts," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 39(4), pages 841-62, November.
When requesting a correction, please mention this item's handle: RePEc:cpb:discus:92. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: ()
If references are entirely missing, you can add them using this form.