Specific star-formation rate against hard X-ray luminosity for X-ray selected AGNs. The grey, blue, green and red symbols refer to z < 1.120, 1.120 < z < 1.615, 1.615 < z < 2.455 and z > 2.455, respectively. The error-bars and their associated lines refer to the mean luminosities and specific SFRs of the high- and low-luminosity bins within each redshift bin, using the Kaplan-Meier estimator (see Sect. 4.1). We do not detect a significant correlation between the X-ray luminosity and sSFR for the lowest redshift bin, but do detect a significant correlation for higher redshifts (z ≳ 1).