Approximate calculation of corrections at NLO and NNLO

Abstract

For processes involving structure functions and/or fragmentation functions, arguments that there is a part that dominates the NLO corrections are briefly reviewed. The arguments are tested against more recent NLO and in particular NNLO calculations.

Comments: 4 pages, 3 figures, presented at "QCD 2000", Montpellier, France, 5-12 July 2000