Behavior of radio power P_ν in units of W as function of Kellermann’s parameter . Symbol coding corresponds to different radio morphologies and to different STs. Triangles: RL FRII; squares: RL CD, exagons: CD RI, circles: CD RQ. Red: union of B1⁺⁺ and B1⁺, orange: B1, gray: A1, pale blue: A2, xA: blue. The lines trace unweighted least square fits for Pop. B sources (red) and for xA sources considered over the three radio loudness classes.