Boosted Top Jet Tagging at CMS

Multiple techniques for reconstructing highly Lorentz-boosted, hadronically-decaying top quarks are studied. These techniques, including the CMS Top Tagger, the HEP Top Tagger, and N-subjettiness, use jet substructure and jet mass observables to identify ``top-jets''. The efficiency and misidentification rate of these algorithms are compared, both with and without identification of b-quark subjets. The efficiency is measured in data and in simulation, and the ratio of these measurements is presented as a data-simulation scale factor.