Contents 1Introduction2 1.1HowdoWeTrainDeepArchitectures?5 1.2IntermediateRepresentations:SharingFeaturesand AbstractionsAcrossTasks7 1.3DesiderataforLearningAI10 1.4OutlineofthePaper11 2TheoreticalAdvantagesofDeepArchitectures13 2.1ComputationalComplexity16 2.2I