  We report on a study of the ratio of inclusive three-jet to inclusive two-jet
production cross sections as a function of total transverse energy in p-pbar
collisions at a center-of-mass energy sqrt{s} = 1.8 TeV, using data collected
with the D0 detector during the 1992-1993 run of the Fermilab Tevatron
Collider. The measurements are used to deduce preferred renormalization scales
in perturbative O(alpha_s^3) QCD calculations in modeling soft-jet emission.
