This week, we welcome Nicolas Flammarion from EPFL to give a talk in our OxCSML seminar. Please find the details below.
Saif & Hai-Dang.
Speaker: Nicolas Flammarion, Assistant Professor in Computer Science at EPFL
Time and date: 14.00 - 15.00 Friday 11 Nov
Place: Room LG.03 (Small Lecture Theatre), Department of Statistics
Title: Saddle-to-saddle dynamics in diagonal linear networks
Abstract:
When training neural networks with gradient methods and small weight
initialisation, peculiar learning curves are observed: the training
initially shows minimal progress, which is then followed by a sudden
transition where a new "feature" is rapidly learned. This pattern is
commonly known as incremental learning. In this talk, I will demonstrate
that we can comprehensively understand this phenomenon within the
context of a simplified network architecture. In this setting, we can
establish that the gradient flow trajectory transitions from one saddle
point of the training loss to another. The specific saddle points
visited, as well as the timing of these transitions, can be determined
using a recursive algorithm that is reminiscent of the LARS method used
in computing the Lasso path.
Zoom:
https://zoom.us/j/92081686303?pwd=b3Nqa3RydzNkVEZwYjNJU3owWEt4Zz09