  A simple transit model is described along with tests of this model against
published results for 4 exoplanet systems (Kepler-1, 2, 8, and 77). Data from
the Kepler mission are used. The Markov Chain Monte Carlo (MCMC) method is
applied to obtain realistic error estimates. Optimization of limb darkening
coefficients is subject to data quality. It is more likely for MCMC to derive
an empirical limb darkening coefficient for light curves with S/N (signal to
noise) above 15. Finally, the model is applied to Kepler data for 4 Kepler
candidate systems (KOI 760.01, 767.01, 802.01, and 824.01) with previously
unpublished results. Error estimates for these systems are obtained via the
MCMC method.
