Demand Forecasting with Amazon Forecast - Ingesting Time Series Data and Improving Prediction Accuracy
Learn how to build time series forecasting models with Forecast, leverage related data, and export prediction results.
Forecast Overview
Forecast is an ML-based time series forecasting service that predicts future values from up to 5 years of historical data. You input time series data such as past sales data, web traffic, and inventory data, and it automatically builds models to predict future values. It leverages the same ML algorithms used for demand forecasting at Amazon.com, and AutoML automatically selects the optimal model. It provides probabilistic forecasts with P10, P50, and P90 prediction intervals.
Data Preparation and Forecasting
In addition to target time series data (historical data of the forecast target), adding related time series data (weather, promotion status, pricing) and item metadata (category, brand) improves prediction accuracy. AutoML builds models with multiple algorithms including DeepAR+, Prophet, and ETS, then automatically selects the most accurate model through backtesting. Probabilistic forecasts provide three prediction values: P10 (optimistic), P50 (standard), and P90 (pessimistic). For inventory planning, use P90 to reduce the risk of stockouts.
Improving Prediction Accuracy and What-If Analysis
Forecast prediction accuracy depends heavily on input data quality and the richness of related data. Adding related time series data (weather, holidays, promotions) allows the model to learn demand fluctuations caused by external factors, improving accuracy. Item metadata (category, brand, price range) is effective for mitigating the cold start problem (predicting demand for new products). What-If analysis lets you set hypothetical scenarios such as price changes or promotions and simulate their impact on demand. Check the Predictor's backtest results for WAPE (Weighted Absolute Percentage Error) and RMSE to quantitatively evaluate prediction accuracy. For practical techniques related to Forecast, you can also check out related books on Amazon.
Forecast Pricing
Forecast pricing consists of generated forecasts, data storage, and training time. Forecasts cost approximately $0.60 per 1,000 forecasts, and data storage costs approximately $0.088 per GB per month. AutoML trains multiple models for automatic algorithm selection, so training costs are higher than when manually specifying an algorithm. If prediction accuracy is sufficient, reduce costs by changing training frequency from weekly to monthly. Set the forecast horizon (prediction period) to the minimum required by business needs and avoid unnecessarily long prediction periods to optimize costs.
Summary
Forecast is a service that automatically builds ML models from time series data to provide demand forecasts. AutoML automatically selects the optimal algorithm, and adding related time series data (weather, promotions) improves prediction accuracy. It provides probabilistic forecasts with P10/P50/P90 prediction intervals and supports scenario-based decision-making through What-If analysis.