H₂O (3₁₂ − 3₀₃)-normalized intensities (in Jy km s⁻¹) as a function of the energy of the upper levels. Colored diamonds are the H₂O line ratios of our three quasars as indicated in the legend at the top of the panel. The red and blue dotted lines are, respectively, the average H₂O SLED of local strong-AGN- and HII+mild-AGN-dominated galaxies reported in Yang et al. (2013). The solid black line is the average SLED of the whole sample with the gray shadowed area representing the 1-σ uncertainty. We also report data retrieved from the literature for the nearby ULIRG Arp 220 (Rangwala et al. 2011), the AGN-dominated galaxy Mrk 231 (González-Alfonso et al. 2010), and the SMG HFLS 3 at z = 6.34 (Riechers et al. 2013). The energy of upper levels of 2₀₂ − 2₁₁ and 3₁₂ − 3₀₃ transitions were shifted for clarity to −15 K and +25 K, respectively. We also slightly shifted the SLEDs of Arp 220, Mrk 231, HFLS 3 horizontally to −5 K, and those of our quasars to +5 K for clarity.