tokens: Theoretical approaches to generalization include classical notions like VC dimension baum1989size , bartlett2017nearly and Rademacher complexity sun2016depth , but also more modern concepts such as stabilitypmlr - v48-hardt16 , robustness xu2012robustness , compressionarora2018stronger as well as studies on the relation between generalization and properties of stochastic gradient descent ( SGD ) algorithms zhangmusings , soudry2017implicit , advani2017high .