SOTAVerified

On First-Order Meta-Learning Algorithms

2018-03-08Code Available1· sign in to hype

Alex Nichol, Joshua Achiam, John Schulman

Code Available — Be the first to reproduce this paper.

Reproduce

Code

Abstract

This paper considers meta-learning problems, where there is a distribution of tasks, and we would like to obtain an agent that performs well (i.e., learns quickly) when presented with a previously unseen task sampled from this distribution. We analyze a family of algorithms for learning a parameter initialization that can be fine-tuned quickly on a new task, using only first-order derivatives for the meta-learning updates. This family includes and generalizes first-order MAML, an approximation to MAML obtained by ignoring second-order derivatives. It also includes Reptile, a new algorithm that we introduce here, which works by repeatedly sampling a task, training on it, and moving the initialization towards the trained weights on that task. We expand on the results from Finn et al. showing that first-order meta-learning algorithms perform well on some well-established benchmarks for few-shot classification, and we provide theoretical analysis aimed at understanding why these algorithms work.

Tasks

Benchmark Results

DatasetModelMetricClaimedVerifiedStatus
Mini-Imagenet 10-way (1-shot)Reptile+BNAccuracy32Unverified
Mini-Imagenet 10-way (1-shot)ReptileAccuracy31.1Unverified
Mini-Imagenet 10-way (5-shot)Reptile+BNAccuracy47.6Unverified
Mini-Imagenet 10-way (5-shot)ReptileAccuracy44.7Unverified
Mini-Imagenet 5-way (1-shot)Reptile + TransductionAccuracy49.97Unverified
Mini-Imagenet 5-way (5-shot)Reptile + TransductionAccuracy65.99Unverified
OMNIGLOT - 1-Shot, 20-wayReptile + TransductionAccuracy89.43Unverified
OMNIGLOT - 1-Shot, 5-wayReptile + TransductionAccuracy97.68Unverified
OMNIGLOT - 5-Shot, 20-wayReptile + TransductionAccuracy97.12Unverified
OMNIGLOT - 5-Shot, 5-wayReptile + TransductionAccuracy99.48Unverified
Tiered ImageNet 10-way (1-shot)ReptileAccuracy33.7Unverified
Tiered ImageNet 10-way (1-shot)Reptile+BNAccuracy35.3Unverified
Tiered ImageNet 10-way (5-shot)ReptileAccuracy48Unverified
Tiered ImageNet 10-way (5-shot)Reptile+BNAccuracy52Unverified

Reproductions