A theory of explanation might treat explanations in either a realist or an epistemic (that is, anti-realist) sense. A realist interpretation of explanation holds that the entities or processes an explanation posits actually exist--the explanation is a literal description of external reality.
Officers in pay grades O-1, O-2, and O-3 with more than four years of prior cumulative service in an enlisted or warrant officer grade are paid increased wages using the special pay grades of O-1E, O-2E, and O-3E, respectively.
Typically, pay grades encompass two dimensions: a vertical range where each level corresponds to the responsibility of, and requirements needed for a certain position; and a horizontal range within this scale to allow for monetary incentives rewarding the employee 's quality of performance or length of service. pay grade is a unit in systems of monetary compensation for employment.