Correlation maps indicating the as a color map for KIC 6928997, as deduced from the asymptotic relation Eq. (17). The one-dimensional marginal distributions are given in Fig. A.5. The levels are indicated by the various colorbars. Top left: correlation map of the marginal two-dimensional parameter space (ΔΠ_1,asym, q). The darkest shade indicates the most likely solution. Bottom left: correlation map of the marginal two-dimensional parameter space (ΔΠ_1,asym, ϵ_g). A strong correlation is observed between the two parameters. Bottom right: correlation map of the marginal two-dimensional parameter space (q, ϵ_g). Correlation maps for the other two stars in our sample are given in the Appendix.