Statistical Methods to Assess the Combined Sensitivity of the ATLAS Detector to the Higgs Boson in the Standard Model

We discuss statistical methods used to assess the combined sensitivity to the Standard Model Higgs boson using the ATLAS detector. The combination is performed using the likelihood ratio as a test statistic. Combined results are calculated using the results of a recent scientific note. Difficulties in calculating the significance using likelihood ratio techniques in the high event rate and high significance environment of the LHC are discussed, and software packages which implement solutions to these problems are presented. We also provide a brief discussion about different ways to incorporate systematic error and introduce the statistical notion of power to the ATLAS Higgs search.