Poissonian parameter, 𝒫 (Eq. (52)), as a function of dynamical group mass, M_dyn, for GAMA galaxy groups with three or more members (blue), and groups with five or more members (white). The orange and green lines show the best-fit power law (Eq. (53)) to the GAMA/2 × 2 pt+SMF data, with the green-shaded region showing the uncertainty on the 2 × 2 pt+SMF fit. The fiducial, single value model for 𝒫 is shown with the grey horizontal band. With the wiggly grey-shaded areas, we show the approximate range of dynamical group masses that are outside the halo mass range of our analysis.