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Shortcut learning in deep neural networks

Abstract

Deep learning has triggered the current rise of artificial intelligence and is the workhorse of today’s machine intelligence. Numerous success stories have rapidly spread all over science, industry and society, but its limitations have only recently come into focus. In this Perspective we seek to distil how many of deep learning’s failures can be seen as different symptoms of the same underlying problem: shortcut learning. Shortcuts are decision rules that perform well on standard benchmarks but fail to transfer to more challenging testing conditions, such as real-world scenarios. Related issues are known in comparative psychology, education and linguistics, suggesting that shortcut learning may be a common characteristic of learning systems, biological and artificial alike. Based on these observations, we develop a set of recommendations for model interpretation and benchmarking, highlighting recent advances in machine learning to improve robustness and transferability from the lab to real-world applications.

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Fig. 1: Examples of shortcut learning.
Fig. 2: Toy example of shortcut learning in neural networks.
Fig. 3: Taxonomy of decision rules.
Fig. 4: Humans and DNNs both generalize, but they generalize very differently.

Code availability

Code to reproduce the toy experiment (Fig. 2) is available at: https://github.com/rgeirhos/shortcut-perspective.

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Acknowledgements

The authors thank the International Max Planck Research School for Intelligent Systems (IMPRS-IS) for supporting R.G. and C.M.; the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) for supporting C.M. via grant EC 479/1-1; the Collaborative Research Center (Projektnummer 276693517—SFB 1233: Robust Vision) for supporting M.B. and F.A.W.; the German Federal Ministry of Education and Research through the Tübingen AI Center (FKZ 01IS18039A) for supporting W.B. and M.B.; as well as the Natural Sciences and Engineering Research Council of Canada and the Intelligence Advanced Research Projects Activity (IARPA) via Department of Interior/Interior Business Center (DoI/IBC) contract number D16PC00003 for supporting R.Z. The authors would like to thank J. Borowski, M. Burg, S. Cadena, A. S. Ecker, L. Eisenberg, R. Fleming, I. Fründ, S. Greiner, F. Grießer, S. Keshvari, R. Kessler, D. Klindt, M. Kümmerer, B. Mitzkus, H. Nienborg, J. Rauber, E. Rusak, S. Schneider, L. Schott, T. Sering, Y. Sharma, M. Tangemann, R. Zimmermann and T. Wallis for helpful discussions.

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The project was initiated by R.G. and C.M. and led by R.G. with support from C.M. and J.J.; F.A.W. added the cognitive science and neuroscience connection; M.B. and W.B. reshaped the initial thrust of the perspective and together with R.Z. supervised the machine learning components. The toy experiment was conducted by J.J. with input from R.G. and C.M. Most figures were designed by R.G. and W.B. with input from all other authors. Figure 2 (left) was conceived by M.B. The first draft was written by R.G., J.J. and C.M. with input from F.A.W. All authors contributed to the final version and provided critical revisions from different perspectives.

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Correspondence to Robert Geirhos.

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Geirhos, R., Jacobsen, JH., Michaelis, C. et al. Shortcut learning in deep neural networks. Nat Mach Intell 2, 665–673 (2020). https://doi.org/10.1038/s42256-020-00257-z

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