Thirty-five scientists signed a letter addressed to the EPA Administrator, the Honorable Lisa P. Jackson, on October 7 2009 expressing concern that proposed rulemaking on the regulation of greenhouse gases would be based on unscientific forecasting procedures. Read more about the letter on the Public Policy Forecasting pages.

World leaders gathered in New York are being lambasted by the UN with predictions of dire climate consequences if they fail to institute costly policies against CO2 emissions. Meanwhile, 20 months ago Scott Armstrong challenged Al Gore, an advocate of the UN forecasts, to bet the UN Intergovernmental Panel of Climate Change's projection that global mean temperatures would be 0.3 degrees Celsius warmer in ten years time against the scientific benchmark forecast that there would be no change in global mean temperatures. Al Gore declined the bet but, had he taken it, he would have lost 18 out of the first 20 months of the bet. For graphs recording the predictions and outcome to-date see the See also the graph showing a third-party prediction market on who will win the bet; participants favor the scientific approach to forecasting global temperatures giving Armstrong a 73% chance of winning.

Robert Fildes's Bibliography of Business and Economic Forecasting is now available in Endnote and RTF formats. See the Researchers Pages.

In a cheekily titled article--"Forecast: Next Year Will Arrive in 2010-ish"--Carl Bialik asks experts, including Foresight editor Len Tashman and directors Scott Armstrong and Kesten Green, why forecasts for 2009 have been so wrong. His article is subtitled "Recession Clouded Crystal Balls in Many Industries, Prompting Predictors to Regroup, Change Strategies and Exercise Caution" signaling his disappointment. In their essay "How to Forecast for Recessions and Recoveries" (on ManyWorlds; original) Armstrong and Green suggest using a simple rule from Collopy and Armstrong's Rule-based Forecasting in order to avoid embarrassment: When a time series is identified as “contrary,” do not extrapolate a trend.

Can you help us to improve the site by making a donation towards improving the functionality of the site's free Delphi Software forecasting tool?

You may have noticed the new "Donate" tab in the banner at the top of the site. The Forecasting Principles site is provided as a public service for forecasters, researchers, teachers, students, and the consumers of forecasts. To provide this service, including the Special Interest Groups, we depend on sponsorship and advertising. Sponsorship was initially provided by The Wharton School. In more recent years, the International Institute of Forecasters has been and continues to be a generous sponsor and the site's key supporter.

The site's current revenue is not, however, sufficient to cover the cost of improving, extending, and developing forecasting support software tools such as the Delphi Software. For example, users of the Delphi software have asked for the ability to modify questions and change reporting, and to obtain more of the data that is collected in different formats.

Please check out the Donate page. Even a $10 donation would help us to keep improving the site for you.

Scott Armstrong
Kesten Green