Result range

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The result range of a variable contains all possible values that the result of the variable may get with probability P>0. The result range is restricted by logical (the number of actual individuals must be an integer), rational (concentration cannot be negative or above 1000 g/kg), and observational (TCDD concentration in humans has never been observed to be above 144000 ng/kg fat) statements. The utility of result range comes from the dependencies to other variables. Child variables are probability distributions conditional on their parents. If the result range of the parents is defined and more or less unchanged, it facilitates the definition process of the children. The conditional probability distribution of a child is only defined for the parent values within its result range.

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Should 'Result range' be a sub-attribute of 'Definition' in a variable? Alternative solution: it is discussed under 'Data', because in practice, the result range is based on Data. Third alternative: it is put under 'Result', maybe as a sub-attribute; this is not a good idea, because the result range has implications on e.g. 'Formula', and it is not good if the result affects Definition.

→ Because clear understanding does not yet exist, the attribute structure is not changed, and the result range is described under 'Data'. R↻

Scope

How can a plausible result range for a variable be found? What are the criteria for inclusion or exclusion of a particular value or range?

Definition

Rationale

In expert judgement, it is a common practice to define the result range by calculating the difference between the fractiles 0.05 and 0.95, extend that by k % (k is often 10 % or found by optimising), and subtract it from and add it to the fractiles 0.05 and 0.95, respectively.

In open assessment, all values are included in the result range by default. A suggested procedure is to exclude any range X that passes a critical argumentation about the exclusion. The argumentation has a statement of the following form: "It is impossible that the result of the variable may be within range X." If the statement is accepted, X is excluded from the result range. R↻

Procedure

All values are included in the result range by default. Any range X that passes a critical argumentation about the exclusion will be excluded. The argumentation has a statement of the following form: "It is impossible that the result of the variable may be within range X." If the statement is accepted, X is excluded from the result range.

See also