  Time delay estimation (TDE) is a well-known technique to investigate poloidal
flows in fusion plasmas. The present work is an extension of the earlier works
of A. Bencze and S. Zoletnik 2005 and B. T\'al et al. 2011. From the
prospective of the comparison of theory and experiment it seem to be important
to estimate the statistical properties of the TDE based on solid mathematical
groundings. This paper provides analytic derivation of the variance of the TDE
using a two-dimensional model for coherent turbulent structures in the plasma
edge and also gives an explicit method for determination of the tilt angle of
structures. As a demonstration this method is then applied to the results of a
quasi-2D Beam Emission Spectroscopy (BES) measurement performed at the TEXTOR
tokamak.
