Fourier terms for long seasonal cycles

Advanced forecasting should be judged by horizon, segment and decision value—not one aggregate score. This note examines fourier terms for long seasonal cycles with that evaluation discipline.

Practitioner lens

Model fourier terms for long seasonal cycles at the granularity the business needs, but inspect whether reconciliation or aggregation changes bias, variance or the shape of the predictive distribution.

First experiment

Report uncertainty, compute cost and maintenance burden alongside point accuracy.

This is an original educational brief. It is a starting point for discussion, not a claim that one technique fits every supply chain.