An inference is admissible if and only if all three conditions hold
Louis Morissette
Abstract
This document defines the DECISION layer of the COS45 framework. It formalizes the admissibility condition used to determine whether an inference is justified under noise-constrained observations. The decision rule is based on the detectability margin:η = δ − τ where δ represents observable structure derived from data, and τ represents the uncertainty threshold. An inference is admissible if and only if the following conditions hold:η > 0, T = 1, and R ≥ R_min. This is a decision rule, not a statement of existence. The DECISION layer evaluates detectability, not the existence of underlying structure. All admissibility outcomes are contingent on observable inputs and uncertainty estimates. This document does not define observable quantities, does not introduce new mathematical results, and does not model system dynamics. These elements are defined in other layers of the COS45 framework. Its role is to act as the admissibility gate between observable measurements and applied inference. Version (v2.0) formalizes the admissibility condition and clarifies the separation between detectability and existence. No change to underlying definitions.