Date of this Version
Journal of Business Research
This article proposes a unifying theory, or the Golden Rule, or forecasting. The Golden Rule of Forecasting is to be conservative. A conservative forecast is consistent with cumulative knowledge about the present and the past. To be conservative, forecasters must seek out and use all knowledge relevant to the problem, including knowledge of methods validated for the situation.
Twenty-eight guidelines are logically deduced from the Golden Rule. A review of evidence identified 105 papers with experimental comparisons; 102 support the guidelines. Ignoring a single guideline increased forecast error by more than two-fifths on average. Ignoring the Golden Rule is likely to harm accuracy most when the situation is uncertain and complex, and when bias is likely. Non-experts who use the Golden Rule can identify dubious forecasts quickly and inexpensively.
To date, ignorance of research findings, bias, sophisticated statistical procedures, and the proliferation of big data, have led forecasters to violate the Golden Rule. As a result, despite major advances in evidence-based forecasting methods, forecasting practice in many fields has failed to improve over the past half-century.
Originally published in Journal of Business Research © 2015 Elsevier
This is a pre-publication version. The final version is available at http://dx.doi.org/10.1016/j.jbusres.2015.03.031
analytics, bias, big data, causality, checklists, combining, elections, index method, judgmental bootstrapping, structured analogies, uncertainty
Armstrong, J. S., Green, K. C., & Graefe, A. (2015). Golden Rule of Forecasting: Be Conservative. Journal of Business Research, 68 (8), 1717-1731. http://dx.doi.org/10.1016/j.jbusres.2015.03.031
Available for download on Saturday, September 01, 2018
Date Posted: 15 June 2018
This document has been peer reviewed.