Correlation function measurements. Top panel: AGN–galaxy cross-correlation function (black points) and galaxy auto-correlation function (orange points) for the combined XXL and Stripe 82X samples, shown together with their best-fitting models (solid lines). Middle and bottom panels: Same measurements performed separately for each field, compared with the combined results. The corresponding DMH mass estimates for each field and for the merged dataset are listed in Table 2. Data points have been offset in the x-axis for clarity.