Top: marginal constraints on the dipole modulation amplitude, as derived from Planck 2015 temperature observations at a smoothing scale of 5° FWHM for Commander (red), NILC (orange), SEVEM (green), and SMICA (blue). The plot corresponds directly to Fig. 32 of Planck Collaboration XXIII (2014). The Commander, SEVEM, and SMICA posteriors coincide almost perfectly both internally, and with the corresponding SMICA 2013 posterior, shown as a dashed black line. Bottom: corresponding marginal two-dimensional constraints on the low-ℓ power spectrum amplitude and tilt, (q,n), defined relative to the best-fit Planck 2015 ΛCDM model.