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Judgmental forecast

As explained in Demand Forecasting Best Practices

A judgmental forecast is a prediction of future demand that incorporates human assessment rather than relying solely on an automated forecasting model.

A judgmental forecast enriches an automated forecast baseline with human information that the forecasting model does not know. It belongs within demand planning rather than replacing the forecast engine entirely. section 16.0

Use judgment to address information outside the model, especially when:

  • A major customer expects unusually low sales. section 16.1
  • A new product lacks sufficient history for the model to forecast accurately. section 16.1
  • A future price change or major market-condition shift is absent from the model’s inputs. section 16.1
  • A trend or seasonality appears wrong, first investigate and improve the forecasting model rather than repeatedly editing individual forecasts. section 16.1

Track forecast value added to assign ownership and accountability and to test whether judgment improves the process. The metric monitors value, but does not by itself explain poor edits or guide their correction. section 16.0

A practical boundary

Reduce the baseline when a key customer signals lower demand or when an unmodeled price increase is planned. Do not override an established trend merely because it feels too low; let the engine handle patterns it already represents. section 16.1

Treat judgmental forecasts cautiously: cognitive biases, incentive-driven intentional biases, and biased processes can distort adjustments. Keep the forecast distinct from a financial budget, sales target, or production and supply plan. section 16.2

Figure 16.1 Example of a demand planning process

Use the demand-planning process figure to see where human enrichment fits around the forecast baseline. section 16.0

Figure 16.2 Sources of judgmental biases

Use the bias figure to inspect cognitive, intentional, and process-related sources of judgmental distortion. section 16.2

How Demand Forecasting Best Practices covers it

How deep it goes
Explains use cases, accountability through forecast value added, and bias sources, but stops short of detailed editing procedures.
Examples
Uses customer signals, new products, pricing changes, market shifts, trends, and seasonality to distinguish useful edits from poor ones.
What it assumes
Assumes familiarity with forecasting models and distinguishes demand forecasts from budgets, sales targets, and supply plans.
What you can do after
Apply it by enriching forecasts with unmodeled information and tracking whether stakeholder adjustments add value.
How it connects
Connects demand planning with forecasting models, forecast value added, cognitive bias, intentional bias, and biased processes.

Related concepts

This explainer was generated by Manning's knowledge graph from the text of Demand Forecasting Best Practices. The section links point to the parts of the book it draws on.