Authors: Annastiina Kerkkänen; Janne Huiskonen
Addresses: Department of Industrial Management, Supply Chain and Operations Management, Lappeenranta University of Technology, P.O. Box 20 FIN-53851 Lappeenranta, Finland ' Department of Industrial Management, Supply Chain and Operations Management, Lappeenranta University of Technology, P.O. Box 20 FIN-53851 Lappeenranta, Finland
Abstract: The paper deals with clarifying the role of contextual information in demand forecasting. Both judgemental and statistical forecasting methods are often needed to provide accurate forecasts. However, in practice it is often difficult to tell when judgemental intervention is needed and when it is not. This paper presents a case example about judgemental forecasting, in which the forecaster has different pieces of information available for the basis of a forecast. The paper provides some guidelines on how to evaluate the value of contextual information with probability calculations. The calculations show that in some situations, it is impossible to improve forecast accuracy, even though the contextual information is seemingly valuable. With probability calculations, it is possible to give more objective and specific rules on when contextual information is useful in forecasting and when it is not. This can help in selecting proper forecasting methods, and setting more realistic accuracy targets.
Keywords: demand forecasting; contextual information; judgemental forecasting; judgemental adjustment; probability calculations; forecast accuracy.
International Journal of Information and Decision Sciences, 2014 Vol.6 No.2, pp.109 - 126
Available online: 28 May 2014 *Full-text access for editors Access for subscribers Purchase this article Comment on this article