From the question to the decision file.

Frame the question

Write down the decision, the options, the status quo, the offer-segment-channel-area unit, the horizon, the constraints and the owner. An unframed question produces results that cannot be compared. The expected level of evidence is set before the calculation.

Investigate

Choose the measurement compatible with the decision, document the data, make the calculation reproducible, and test the assumptions capable of reversing the choice.

Decide and revise

Compare the options on the same definitions, publish the uncertainty, name the decision rule, and set a signal, a threshold and a revision date.

• Compare the families of methods
• Understand the hierarchy of sources

Evidence levels E0 to E3

E0 qualifies a proposition or a working grid. E1 documents an attributable fact. E2 frames a calculation or an estimate with formula, units, assumptions and sensitivity. E3 concerns a scientific or causal conclusion and requires a verified full text, estimand, design, uncertainty and transport limits.