Behavior of the centroid at 1/2 of total C1549 profile as a function of Eddington ratio. Hexagons represent the GTC-xA sample. The colors of hexagons are the same as Figs. 2 and 3. Blue and red pale symbols correspond to the Population A and B, respectively. Squares and stars correspond to the FOS-A and xA samples (Sulentic et al. 2007). Circles are from HE sample Sulentic et al. (2017) sample. Yellow star marks the position of I Zw 1. The black dashed horizontal line indicates km s. Gray and black dashed vertical lines indicate = 0.2 and 1.0, respectively.