Missing data effects: mean shear two-point correlation function ξ₊ (black) and corresponding mean convergence two-point correlation function ξ_κE reconstructed using the KS method (blue) and using the KS+ method (red) from incomplete shear maps. The estimation is only made outside the mask M. The shaded area represents the uncertainties on the mean estimated on 1000 deg². Lower panel: relative two-point correlation errors introduced by missing data effects, that is, the normalised difference between the upper curves.