1. See, e.g., the web-site
http://www.pwc.co.uk/economic-services/global-economy-watch/gew-projections.jhtml
of PricewaterhouseCoopers as an example of “economic forecasts” two years into the future.
2. Toth, Z., Kalnay, E.: Ensemble forcasting at NMC: the generation of perturbations. Bull. Am. Meteorol. Soc. 74, 2317 (1993)
3. Brier, G.: Verification of forecasts expressed in terms of probability. Mon. Weather Rev. 78, 1 (1950)
4. Christensen, H.M., Moroz, I.M., Palmer, T.N.: Evaluation of ensemble forecast uncertainty using a new proper score: application to medium-range and seasonal forecasts, Q. J. R. Meteorol. Soc. (2014). doi:10.1002/qj.2375
5. Mailier, P.J., Jolliffe, I.T., Stephenson, D.B.: Quality of weather forecasts. Online publication of the Royal Meteorological Society (2006). Available through the publication lists of its authors, e.g.
http://empslocal.ex.ac.uk/people/staff/dbs202/publications/booksreports/mailier.pdf