  The statistical properties of the $E \times B$ flux in different types of
plasma turbulence simulations are investigated using probability density
distribution functions (PDF). The physics included in the models ranges from
two dimensional drift-wave turbulence to three dimensional MHD simulations. The
PDFs of the flux surface averaged transport are in good agreement with an
extreme value distribution (EVD). This is interpreted as a signature of
localized vortical structures dominating the transport on a flux surface.
Models accounting for a local input of energy and including the global
evolution of background profiles show a more bursty behavior in 2D as well as
3D simulations of interchange and drift type turbulence. Although the PDFs are
not Gaussian, again no algebraic tails are observed. The tails are, in all
cases considered, in excellent agreement with EVDs.
