bars on the data points were rescaled to give a $\chi^{2}_{\nu}$ = 1. $\beta$ quantifies how the measured noise deviates from pure Gaussian white noise (solid black lines).[]{data-label="fig:rms_vs_bins"}](rms_vs_bins.pdf)

Unocculted spots {#sec:unocculted}
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Just as the effects of occulted spots or bright regions must be taken into account when calculating the planetary radius, so must the effects of those regions which are not seen in the transit. As the photometric modulation of Sun-like stars with high magnetic activity is dominated by dark spots (e.g. @Shapiro2014), we only consider the effect of unocculted spots on our derived transit depths. Unocculted spots cause the observed stellar flux to decrease, increasing the transit depth as compared to a spot free surface. This effect needs to be taken into account with a wavelength dependent depth correction.

Following the formalism of [@Sing2011], the variation in transit depth, $\Delta d/d$, can be related to the fractional decrease of the stellar flux due to unocculted spots at a reference wavelength $\lambda_0$, $\Delta f(\lambda_{0},t)$, the flux of the pristine stellar disc, $F_{\lambda}^{T_{star}}$, and the flux of the spot, $F_{\lambda}^{T_{spot}}$, through

$$\frac{\Delta d}{d} = \Delta f(\lambda_{0},t) \left(1 - \frac{F_{\lambda}^{T_{spot}}}{F_{\lambda}^{T_{star}}}\right)/\left(1 - \frac{F_{\lambda_0}^{T_{spot}}}{F_{\lambda_0}^{T_{star}}}\right)$$

leading to a variation in the ratio of planet 