Transmission spectra of KIC 10657664B calculated using different noise models (left column: GP-M32 model. Right column: best-fit BF model), different reference stars (REF-A1 to A4 from the top row to the bottom row), and different common-mode removal techniques (direct-fit: blue circles; divide-white: green squares; divide-rescaled: red diamonds). The solid lines and shaded areas are the best-fit polynomials with the strongest Bayesian evidence and their 1er credible intervals, respectively. The black horizontal lines are the broadband radius ratio from the Kepler data. The data points are slightly shifted along the wavelength for clarity.