/leo

Implementation of Meta-Learning with Latent Embedding Optimization

Primary LanguagePythonApache License 2.0Apache-2.0

Meta-Learning with Latent Embedding Optimization

Overview

This repository contains the implementation of the meta-learning model described in the paper "Meta-Learning with Latent Embedding Optimization" by Rusu et. al. It was posted on arXiv in July 2018 and will be presented at ICLR 2019.

The paper learns a data-dependent latent representation of model parameters and performs gradient-based meta-learning in this low-dimensional space.

The code here doesn't include the (standard) method for pre-training the data embeddings. Instead, the trained embeddings are provided.

Disclaimer: This is not an official Google product.

Running the code

Setup

To run the code, you first need to need to install:

Getting the data

You need to download the embeddings and extract them on disk:

$ wget http://storage.googleapis.com/leo-embeddings/embeddings.zip
$ unzip embeddings.zip
$ EMBEDDINGS=`pwd`/embeddings

Running the code

Then, clone this repository using:

$ git clone https://github.com/deepmind/leo

and run the code as:

$ python runner.py --data_path=$EMBEDDINGS

This will train the model for solving 5-way 1-shot miniImageNet classification.

Hyperparameters

To train the model on the tieredImageNet dataset or with a different number of training examples per class (K-shot), you can pass these parameters with command-line or in config.py, e.g.:

$ python runner.py --data_path=$EMBEDDINGS --dataset_name=tieredImageNet --num_tr_examples_per_class=5 --outer_lr=1e-4

See config.py for the list of options to set.

Comparison of paper and open-source implementations in terms of test set accuracy:

Implementation miniImageNet 1-shot miniImageNet 5-shot tieredImageNet 1-shot tieredImageNet 5-shot
LEO Paper 61.76 ± 0.08% 77.59 ± 0.12% 66.33 ± 0.05% 81.44 ± 0.09%
This code 61.89 ± 0.16% 77.65 ± 0.09% 66.25 ± 0.14% 81.77 ± 0.09%

The hyperparameters we found working best for different setups are as follows:

Hyperparameter miniImageNet 1-shot miniImageNet 5-shot tieredImageNet 1-shot tieredImageNet 5-shot
outer_lr 2.739071e-4 4.102361e-4 8.659053e-4 6.110314e-4
l2_penalty_weight 3.623413e-10 8.540338e-9 4.148858e-10 1.690399e-10
orthogonality_penalty_weight 0.188103 1.523998e-3 5.451078e-3 2.481216e-2
dropout_rate 0.307651 0.300299 0.475126 0.415158
kl_weight 0.756143 0.466387 2.034189e-3 1.622811
encoder_penalty_weight 5.756821e-6 2.661608e-7 8.302962e-5 2.672450e-5