  A massive planet closely orbiting its host star creates tidal forces that
distort the typically spherical stellar surface. These distortions, known as
ellipsoidal variations, result in changes in the photometric flux emitted by
the star, which can be detected within the data from the Kepler Space
Telescope. Currently, there exist several models describing such variations and
their effect on the photometric flux. By using Bayesian model testing in
conjunction with the Bayesian-based exoplanet characterization software package
EXONEST, the most probable representation for ellipsoidal variations was
determined for synthetic data and the confirmed hot Jupiter exoplanet
Kepler-13Ab.The most preferred model for ellipsoidal variations observed in the
Kepler-13 light curve was determined to be EVIL-MC. Among the trigonometric
models, the Modified Kane & Gelino model provided the best representation of
ellipsoidal variations for the Kepler-13 system and may serve as a fast
alternative to the more computationally intensive EVIL-MC. The computational
feasibility of directly modeling the ellipsoidal variations of a star are
examined and future work is outlined. Providing a more accurate model of
ellipsoidal variations is expected to result in better planetary mass
estimations.
