  We give a short review of our recent analysis [1] of the deep inelastic
scattering data (provided by BCDMS, SLAC, NMC) on F2 structure function in the
non-singlet approximation with up to next-to-next-to-leading-order accuracy and
analytic and frozen modifications of the strong coupling constant featuring no
unphysical singularity (the Landau pole). Improvement of agreement between
theory and experiment, with respect to the case of the standard perturbative
definition of the strong coupling constant considered recently in [2], was
observed.
