Relation between ν_max and for CoRoT sismo-channel and Kepler δ Scuti stars (blue asterisks, and green triangles, respectively). The black line represents the fitted relation. Purple lines mark the limits of the predicted dispersion due to the gravity-darkening effect. All dashed lines represent the estimated error of the linear fit. Orange diamonds correspond to the 2% of Kepler δ Scuti stars outsidethe limits when taking into account only 1σ error of theirT_eff measurement (see text). We show only a few error bars for clarity.