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The Miracle of Combining Forecasts

Life gifts us very few miracles. So when a miracle happens, we must be prepared to embrace it, and appreciate its worth. Winter Storm PaxIn 1947, in New York City, there was the Miracle on 34th Street.In 1980, at the Winter...

Posted February 16, 2014    

The "Avoidability" of Forecast Error [PART 2]

While I've long advocated the use of Coefficient of Variation (CV) as a quick and dirty indicator of the forecastability of a time-series, its deficiencies are well recognized. It is true that any series with extremely low CV can be forecast quite...

Posted August 8, 2013    

The "Avoidability" of Forecast Error

"Forecastability" is a frequent topic of discussion on The BFD, and an essential consideration when evaluating the effectiveness of any forecasting process. A major critique of forecasting benchmarks is that they fail to take forecastability into...

Posted August 6, 2013    

One-Number Forecasting: A New Worst Practice?

The one-number forecasting concept has been debated for years.Advocates argue that having different groups within the same organization working to different forecasts is insane. You can't have the supply chain building to X, the sales force selling...

Posted April 3, 2013    

Forecasting the Stock Market: Lessons Learned

There is a well recognized phenomenon that combining forecasts, derived from different methods using different sources of information, can improve forecast accuracy. This approach, sometimes called "ensemble forecasting," is available in SAS...

Posted March 12, 2013    

Forecasting Is Harder Than It Looks

Want to make weather forecasting look good? Compare it to predicting the economy. So concludes an ABC News Australia story by finance reporter Sue Lannin, entitled "Economic forecasts no better than a random walk." The story covers a recent...

Posted February 7, 2013    

Simple Methods and Ensemble Forecasting of Elections

Two enduring principles of forecasting are that simple methods can work as well as fancy methods, and that combining (averaging)  forecasts, also known as "ensemble forecasting," will usually result in more accurate predictions than the...

Posted November 9, 2012    

The Predictive Power of Nonsense

The 2012 US Presidential race comes to a close today (thankfully), and there is no shortage of wacky indicators predicting the winner:Iowa Electronic MarketsFiveThirtyEightPollyVoteUniversity of ColoradoIn primitive times a diviner could foretell...

Posted November 7, 2012    

Guest Blogger: Len Tashman Previews Fall 2012 Issue of Foresight

Editor Len Tashman's Preview of ForesightThe importance of trust in the dissemination of forecasts through an organization cannot be overstated. Lack of trust, due in no small measure to the biases arising from “silo mentalities” and misplaced...

Posted November 6, 2012    

Could You Be POTUS?

Business forecasting is a dismal field of endeavor, fit for dismal people like myself. In an attempt to make this field interesting to people who aren't so dismal by nature, our friends at PollyVote Election Forecasting ask the question:Could...

Posted September 28, 2012    

More on Forecasting Benchmarks

The Perils RevisitedA few posts ago I warned of the perils of forecasting benchmarks, and why they should not be used to set your forecasting performance objectives:Can you trust the data?Is measurement consistent across the respondents?Is the...

Posted August 27, 2012    

Forecasting Olympic Medals

The 2012 Summer Olympics in London are just around the corner, and it's sure to be an exciting time for all. I had the good fortune to be living in the great state of Utah during the 2002 Winter Olympics in Salt Lake City, and it was a...

Posted July 16, 2012