  We employ quasiparticle path integral molecular dynamics to study how the
excitonic properties of model semiconductors are altered by electron-phonon
coupling. We describe ways within a path integral representation of the system
to evaluate the renormalized mass, binding energy, and radiative recombination
rate of excitons in the presence of a fluctuating lattice. To illustrate this
approach, we consider Fr\"ohlich-type electron-phonon interactions and employ
an imaginary time influence functional to incorporate phonon-induced effects
nonperturbatively. The effective mass and binding energies are compared with
perturbative and variational approaches, which provide qualitatively consistent
trends. We evaluate electron-hole recombination rates as mediated through both
trap-assisted and bimolecular processes, developing a consistent statistical
mechanical approach valid in the reaction limited regime. These calculations
demonstrate how phonons screen electron-hole interactions, generically reducing
exciton binding energies and increasing their radiative lifetimes.
