Forecast value add (FVA)
Slides done? Here’s the same idea in a bit more depth — the part worth keeping.
In depth: the question that closes the loop
Every other forecasting lesson is about making the forecast better. Forecast value add asks the harder, more honest question: is all that effort actually helping? It measures whether each step you take — the statistical model, the analyst’s adjustment, the manual override — genuinely improves accuracy against a baseline that costs nothing. Sometimes the answer is uncomfortable, and that’s exactly why it’s valuable: it turns “trust me, the model helps” into evidence one way or the other.
Naive is the line in the sand
The benchmark is the simplest forecast imaginable — “this week equals the same week last cycle.” It takes no skill, no model and no time, which is precisely what makes it the right yardstick. Any model, any human tweak, has to beat that free baseline on accuracy to justify its existence. You score the naive forecast, the statistical forecast and the final adjusted forecast over the same period, and the differences tell you where value was added. A positive step earned its keep; a negative step made the forecast worse.
The finding that stings — and why it helps
Study after study finds the same thing: well-meaning manual overrides often destroy value. Gut-feel nudges, “it feels a bit low,” quiet padding for safety — these frequently take a good statistical forecast and degrade it. FVA surfaces that gently, with data rather than blame, and that’s its real power. It lets a planning team retire the effort that doesn’t pay — switch off a model that loses to naive, drop an override step that adds nothing — and confidently defend the steps that genuinely help. It’s how forecasting stops being craft defended by seniority and becomes a discipline defended by evidence.
The principle to remember: benchmark every step against the free, skill-free forecast. Keep what beats naive, cut what doesn’t, and let evidence — not habit or hierarchy — decide.
Quick quiz
Five questions. Pick an answer to each, then check your score.
1. What does forecast value add measure?
FVA checks whether the model, the override, the tweak actually beat doing the simple naive thing.
2. Why is naive the benchmark?
Naive is free and skill-free — the perfect bar for everything else to clear.
3. What does negative FVA at a step mean?
Negative FVA = that step (often a manual override) reduced accuracy versus the step before it.
4. What does FVA frequently reveal about manual overrides?
Gut-feel adjustments and safety padding often destroy value — FVA shows it with data, not blame.
5. What’s the discipline FVA gives a planning team?
FVA turns “trust me” into evidence — retire effort that doesn’t pay, defend what does.
See methods scored against naive in the forecasting methods spreadsheet, or go deeper in The Forecasting Masterclass.