Left panel: results of our MCMC analysis for HAT-P-13 in the Hertzsprung-Russell diagram. Black dots are individual steps in the Markov chain. The dotted line (blue) is the ZAMS. Solid lines (red) are isochrones for ages 6.6 ± 1.2 Gyr. Dashed lines (green) are evolutionary tracks for masses 1.21 ± 0.06 M_⊙. All isochrones and tracks are for [ Fe/H ] _i = 0.47. Right panel: joint posterior distribution for the mass and age and HAT-P-13 from our MCMC analysis.