  Jets plus missing transverse energy is one of the main search channels for
new physics at the LHC. A major limitation lies in our understanding of QCD
backgrounds. Using jet merging we can describe the number of jets in typical
background channels in terms of a staircase scaling, including theory
uncertainties. The scaling parameter depends on the particles in the final
state and on cuts applied. Measuring the staircase scaling will allow us to
also predict the effective mass for Standard Model backgrounds. Based on both
observables we propose an analysis strategy avoiding model specific cuts which
returns information about the color charge and the mass scale of the underlying
new physics.
