Skip to content
Projects

Demand Forecasting PoC

Benchmarked an early vendor demand-forecasting model against ARIMA on ~600 GB of retail sales history.

role
Python Developer
period
2020 – 2021

Problem

A large US retailer weighing an alpha-stage automl-based demand-forecasting model before committing to it.

What was built

  • Analysis of ~600 GB of sales history (BigQuery, three years, apparel).
  • Feature engineering plus training and validation code around the vendor AutoML model.
  • A benchmark against ARMA / ARIMA / ARIMAX and a summary report for the client.

Outcome

The simple ARMA baseline outperformed the alpha-stage vendor model — a data-backed technology assessment delivered before any rollout decision.

Challenges and Lessons

  • Communication is key to project success — even small message counts.
  • Each query against a large dataset has a real cost — a FinOps lesson; use BigQuery’s row-preview instead of a full query when it’s sufficient.
  • Feature engineering often matters more than model choice.
  • Simpler solutions (ARIMAX-class models) can be more accurate and cheaper than very complex ones (AutoML).
  • Before constructing models, one should deeply understand the data and its characteristics.