Remarks on Bellman's Structural Identifiability
Abstract
**Please note that the full text is embargoed** ABSTRACT: This paper remarks on unidentifiable compartmental systems. Emphasis is placed on detecting properties of the system directly from the compartmental diagram without resort to complicated analysis. New concepts are introduced. One is separability, a condition in which two or more parameters enter the identification equations only as a certain combination thereby preventing their identification. Concepts from linear algebra such as span, basis, and dimension are adopted to "parameter spaces". A necessary and sufficient condition for interval identification is presented.