What is an Evidence State?

A number in a business case has no accent. Whether it was measured by a system last night, modelled by an analyst last month or asserted in a corridor five minutes before the meeting, it looks identical on the slide. Organisations rarely suffer from a shortage of facts. They suffer from facts of wildly different quality wearing the same clothes.

An Evidence State is the label that ends the disguise. Every fact carries one of five states: measured, modelled, inferred, stated or unmeasured. An Evidence State makes the quality of a fact a first-class property of the fact itself, carried everywhere the fact travels, so that an assumption can never again impersonate a measurement.

The five states

• Measured. Observed by an instrument or a system: a timesheet total, a logged transaction. The strongest state a fact can hold.
• Modelled. Produced by a method you can inspect and rerun: a cost model, a capacity plan. Strong, but only as strong as its inputs and assumptions.
• Inferred. Concluded from related evidence rather than observed directly: a risk read from surrounding signals.
• Stated. Asserted by a person or a party: a client projection, a supplier promise. Sincere, perhaps, but unverified.
• Unmeasured. Honestly unknown, and labelled as such rather than papered over with a plausible figure.

The ordering of this ladder, and why each rung outranks the next, is the subject of the Evidence Hierarchy. This entry is about something narrower and easily missed: what changes when the state is attached to the fact itself.

A property of the fact, not a footnote

The important design decision is where the label lives. A caveat in a footnote dies with the slide it was written on. An evidence state lives on the fact, survives every version of it, and is read by everything downstream. That placement has a consequence: confidence stops being a feeling. When confidence is weighted by evidence quality, a conclusion built on measured facts is systematically worth more than the same conclusion built on stated ones, and when a fact is re-versioned, upgraded from stated to measured, or downgraded when its source goes stale, every confidence figure resting on it moves without anyone remembering to update a document.

It also gives improvement a price list. If the dimension that binds a decision rests on a stated fact, the cheapest way to raise confidence is rarely more analysis of the same inputs. It is upgrading that one fact: measuring the thing that has only ever been asserted.

The state at the moment of decision also becomes part of the record. Which facts, in which states, fed which recommendation is the backbone of Decision Provenance: you cannot audit a decision if you cannot see how good its inputs were at the time.

Why labelling changes behaviour

The effects are behavioural before they are technical.

• Impersonation ends. The most dangerous numbers in any business case are stated ones formatted like measured ones. The label removes the costume, without banning the number.
• “Unmeasured” becomes a sayable word. When the honest state of knowledge has an official name, admitting ignorance stops being a career risk and starts being a data point, and the gap it marks becomes visible work rather than a hidden liability.
• Arguments change subject. Instead of debating whose number is right, the room asks which piece of evidence would upgrade the weakest state on the dimension that binds the decision. That is a question with a budget and an owner.

One concrete example

Illustrative only. Consider a pricing review for a large renewal. The cost side is measured from payroll and timesheets. The client volume projections are stated; they come from the client’s own deck. The second-year efficiency gain is modelled, and the churn risk is inferred from engagement signals. In an unlabelled spreadsheet, these four blend into one margin figure that looks equally solid everywhere. With evidence states attached, the same review changes character: the case is strong exactly where it is measured and thin exactly where it leans on the client’s stated volumes. The room stops relitigating the margin and asks a better question: what would it take to measure the volumes before signature? The label added no new information. It stopped the existing information being laundered.

That is the quiet power of the state as a first-class property. It does not make facts better. It makes their quality impossible to ignore, and everything built on them honest about what it is built on.