  In an effort to understand the fundamental physics of turbulent transport of
particles and heat in a tokamak, the floating potential fluctuations in the the
scrape-off layer plasma of ohmically heated ADITYA tokamak are analysed for
self-similarity using distribution function approach. It is observed that the
distribution function of a sum of n data points converges to a Levy
distribution of scale index, alpha=1.111 for n < 40 and alpha=2.0 for larger n.
In both scaling ranges, the edge fluctuation is self-similar. This observation
is backed by several supporting evidences. The results indicate that the small
scale fluctuations transport matter and heat dominantly by convection whereas
the transport due to large scale flucuations is by a diffusive process.
