Top row: pair-wise relationship between the fitting parameters, α₀, ν_char and γ in Eq. (1) shown for stars in our sample with spectroscopic parameters and sufficient CoRoT data for an accurate background fit. Bottom row: location of stars in the (spectroscopic) HR diagram as filled circles that have been colour-coded by the red-noise fit (Eq. (1)) parameters ν_char (left) and γ (right), with the size of each symbol corresponding to the fit parameter α₀. The location of stars with insufficient CoRoT data for an accurate background fit to the residual power density spectrum are shown as white triangles. Evolutionary tracks for representative masses (in units of M_⊙) from Ekström et al. (2012) are shown as solid grey lines, with the dashed grey line representing the ZAMS.