A full Value-Decision-Impact-Estimate includes the following: a Scale-Impact, a Percentage-Impact and uncertainty data (known Error margins). The additional related information required to support an Value-Decision-Impact-Estimate includes the evidence, source(s) and Credibility.
1. An Value-Desicion-Impact-Estimate can be positive, neutral or negative (undesirable in relation to stated target Levels).
2. Note the distinction between a Scale-Impact (an absolute numeric value on a Scale), and a Percentage-Impact (the percentage improvement estimated to be achieved in moving from the chosen Baseline towards the chosen target).
3. An Value-Decision-Impact-Estimate is usually concerned with the System improvement,
rather than with Stakeholder value (However, this Depends-On the choice of
Requirement Attribute: Stakeholder value can be tackled, for example,
4. An Value-Decision-Impact-Estimate is usually on a Scalar Requirement. However, much more rarely, it can be on a Binary Requirement of the System (that is on a Function-Requirement, a Design-Constraint or a Condition-Constraint). This is used in situations where an explicit Check is considered necessary to help evaluate Design-Ideas.
This Concept entered by Kay Dudman.