Impact of the level of magnetic activity on the height of oscillations. Left: chromospheric emission index S_CaII (colorscale and symbol size) as a function of oscillations frequency at maximum amplitude v_max (x-axis) and height of the Gaussian envelope employed to model the oscillation excess power H_max (y-axis) for the 3008 red giants observed both by Kepler and LAMOST, for which S_ph and v_max are available. The colorscale was cut at 0.4 for readability purposes, despite a few points reaching S_CaII ≈ 0.8. Right: corresponding figure for S_ph as measured by Gaulme et al. (2020).