What is exponential smoothing in time series forecasting?

Updated May 15, 2026

Short answer

Exponential smoothing forecasts by giving exponentially decreasing weights to older observations.

Deep explanation

Exponential smoothing methods assign more importance to recent observations while gradually reducing influence of older data. Variants include simple, Holt’s linear, and Holt-Winters (which includes seasonality). It is computationally efficient and widely used in demand forecasting.

Real-world example

Retail demand forecasting with seasonality adjustments.

Common mistakes

  • Ignoring trend or seasonality when selecting smoothing type.

Follow-up questions

  • What is Holt-Winters method?
  • Why use exponential decay weights?

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