ABSTRACT
Close binary stars show regular patterns of light variation that can often be explained in the same, or a similar, way to Goodricke's first hypothesis about Algol raised in Chapter 1. It is useful to have this picture in mind as a preliminary to modelling, but the issues now before us concern the optimal fitting of an appropriately formulated model to a set of observations (cf. Section 1.3). The two main issues in this are the physical basis of the modelling and the analytical procedure.
