  The deep inelastic scattering data on the nucleon F_2 structure function,
accumulated by BCDMS, SLAC and NMC collaborations in fixed-target experiments,
are analyzed in the non-singlet approximation within the frameworks of both
conventional \overline{\mathbf{MS}} scheme as well as those with resummations
of logarithms at large Bjorken x values. The use of the latter is important
because they greatly modify the values of the twist four corrections while
leaving a strong coupling constant almost intact.
