Log-linear plot of diffusion coefficient, D, versus diffusion index, γ. Black crosses indicate the diffusion parameters calculated from trajectories of the Sunrise Ca ii H MBPs. The green, dashed line shows a power-law fit to the data points (see main text). The red solid curve is obtained from a Monte Carlo simulation. Error bars to the simulated values are depicted by blue vertical lines (see Sect. 4.2 for details).