Understanding Global Loss Landscape of One-hidden-layer ReLU Networks,
Part 2: Experiments and Analysis
- URL: http://arxiv.org/abs/2006.09192v1
- Date: Mon, 15 Jun 2020 10:50:47 GMT
- Title: Understanding Global Loss Landscape of One-hidden-layer ReLU Networks,
Part 2: Experiments and Analysis
- Abstract summary: We first analyze how big the probability of existing local minima is for 1D Gaussian data and how it varies in the whole weight space.
We then design and implement a linear programming based approach to judge the existence of genuine local minima.
We find that there are no bad differentiable local minima almost everywhere in weight space once some hidden neurons are activated by samples.
- Score: 4.976129960952446
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The existence of local minima for one-hidden-layer ReLU networks has been
investigated theoretically in [8]. Based on the theory, in this paper, we first
analyze how big the probability of existing local minima is for 1D Gaussian
data and how it varies in the whole weight space. We show that this probability
is very low in most regions. We then design and implement a linear programming
based approach to judge the existence of genuine local minima, and use it to
predict whether bad local minima exist for the MNIST and CIFAR-10 datasets, and
find that there are no bad differentiable local minima almost everywhere in
weight space once some hidden neurons are activated by samples. These
theoretical predictions are verified experimentally by showing that gradient
descent is not trapped in the cells from which it starts. We also perform
experiments to explore the count and size of differentiable cells in the weight
space.
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