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arXiv · 2407.17920

Tobit Exponential Smoothing, towards an enhanced demand planning in the presence of censored data

Diego J. Pedregal·Juan R. Trapero·Enrique Holgado
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Abstract

ExponenTial Smoothing (ETS) is a widely adopted forecasting technique in both research and practical applications. One critical development in ETS was the establishment of a robust statistical foundation based on state space models with a single source of error. However, an important challenge in ETS that remains unsolved is censored data estimation. This issue is critical in supply chain management, in particular, when companies have to deal with stockouts. This work solves that problem by proposing the Tobit ETS, which extends the use of ETS models to handle censored data efficiently. This advancement builds upon the linear models taxonomy and extends it to encompass censored data scenarios. The results show that the Tobit ETS reduces considerably the forecast bias. Real and simulation data are used from the airline and supply chain industries to corroborate the findings.

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Diego J. Pedregal, Juan R. Trapero, Enrique Holgado. 2024-07-25. Tobit Exponential Smoothing, towards an enhanced demand planning in the presence of censored data. https://arxiv.org/abs/2407.17920

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