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Implicit Acceleration and Feature Learning in Infinitely Wide Neural Networks with Bottlenecks

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 نشر من قبل Etai Littwin
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We analyze the learning dynamics of infinitely wide neural networks with a finite sized bottle-neck. Unlike the neural tangent kernel limit, a bottleneck in an otherwise infinite width network al-lows data dependent feature learning in its bottle-neck representation. We empirically show that a single bottleneck in infinite networks dramatically accelerates training when compared to purely in-finite networks, with an improved overall performance. We discuss the acceleration phenomena by drawing similarities to infinitely wide deep linear models, where the acceleration effect of a bottleneck can be understood theoretically.



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