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The Standard Approach (SA) for description of the structure function g_1combines the DGLAP evolution equations and Standard Fits for the initial partondensities. The DGLAP equations describe the region of large Q^2 and large x, sothere are not theoretical grounds to exploit them at small x. In practice,extrapolation of DGLAP into the region of large Q^2 and small x is done withcomplementing DGLAP with special, singular (~x^{-a}) phenomenological fits forthe initial parton densities. The factors x^{-a} are wrongly believed to be ofthe non-perturbative origin. Actually, they mimic the resummation of logs of xand should be expelled from the fits when the resummation is accounted for.Contrary to SA, the resummaton of logarithms of x is a straightforward andnatural way to describe g_1 in the small-x region. This approach can be used atboth large and small Q^2 where DGLAP cannot be used by definition. Confrontingthis approach and SA demonstrates that the singular initial parton densitiesand the power Q^2-corrections (or at least a sizable part of them) are rathernot real physical phenomena but the artefacts caused by extrapolating DGLAPinto the small-x region.

Spin structure function g_1 at small x and arbitrary $Q^2: Total resummaion of leading logarithms vs Standard Approach