Parallel and Intersecting Flats Fractions: Estimability and Alias Structures.

Regular fractional factorial designs may be obtained as solutions sets to linear equations. It is well known how to determine which factorial effects are estimable, and how to construct the alias sets directly from the system matrix. There is no unified theory developed for determining estimability and alias structures from types of fractions involving intersecting flats. The purpose of this paper is to present some preliminary results in the development of such a theory.