In the study of the asymptotic behavior of polynomials from partition theory, the determination of their leading term asymptotics inside the unit disk depends on a sequence of sets derived from comparing certain complex-valued functions constructed from polylogarithms, functions defined as
Li-s(z) = (infinity)Sigma(n=1) z(n)/n(s).
These sets we call phases. This paper applies complex analytic techniques to describe the geometry of these sets in the complex plane.