Modelo composto para prever demanda através da integração de previsões
Composed model to foresee demand through the integration of forecasts
Werner, Liane; Ribeiro, José Luis D.
http://dx.doi.org/10.1590/S0103-65132006000300011
Prod, vol.16, n3, p.493-509, 2006
Resumo
Realizar previsões de demanda é uma atividade importante na empresa, entretanto, usar uma única técnica para obtê-las pode não ser suficiente para incorporar todo o conhecimento associado ao ambiente de previsão. As formas de integração de previsões incorporam várias técnicas e têm mostrado potencial para reduzir o erro de previsão. Este trabalho apresenta uma modelagem que está estruturada utilizando: combinação de previsões e ajuste baseado na opinião. Os elementos incluídos na modelagem são: dados históricos; econômicos; e de especialistas. Após obter-se a previsão combinada, aplica-se um ajuste para obter a previsão final. O modelo proposto é ilustrado através de uma aplicação.
Palavras-chave
Previsão de demanda, combinação de previsões, ajuste baseado na opinião, opinião de especialistas, integração de previsões
Abstract
Demand forecasting is an important task in the companies, however the use of a single technique to produce forecasts might not be enough to gather all the knowledge associated with the forecast environment. The way to integrate forecasts incorporates various techniques and has show potential to reduce forecast error. This study presents a model that relies on the use of two means of integration: forecast combination and judgmental adjustment. The elements covered by the presented model are: historic data, economic data, and the opinion of experts. After obtaining the combined forecast, an adjustment based on the experts' opinion is applied to attain the final forecast. The model proposed is described in details and illustrated through a practical application.
Keywords
Demand forecasting, combination of forecasts, judgmental adjustment, experts opinion, integration of forecasts
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