MELO - Meta-Learning with Adaptive Weighted Loss for Imbalanced Cold-Start Recommendation

A replication of the paper "Meta-Learning with Adaptive Weighted Loss for Imbalanced Cold-Start Recommendation"

Introduction

This repository includes code for training MELO and MAML with various baselines(BERT4REC, SASREC, GRU4REC, NARM). All baseline models are modified to do regression tasks.

References (Codes and Papers)

BERT4REC model reference code: https://github.com/jaywonchung/BERT4Rec-VAE-Pytorch

NARM model reference code: https://github.com/Wang-Shuo/Neural-Attentive-Session-Based-Recommendation-PyTorch

Maml++ reference code: https://github.com/AntreasAntoniou/HowToTrainYourMAMLPytorch

BERT4Rec: Sequential Recommendation with BERT (Sun et al.)

SAS4Rec: Self-Attentive Sequential Recommendation (Kang et al.)

NARM: Neural Attentive Session-based Recommendation (Li et al.)

GRU4Rec: SESSION-BASED RECOMMENDATIONS WITH RECURRENT NEURAL NETWORKS (Hidasi et al.)

METAL: Meta-Learning with Task-Adaptive Loss Function for Few-Shot Learning (Baik et al.)

Dependencies

• pytorch==1.11.0
• tqdm==4.64.0
• numpy==1.12.5
• pandas==1.4.2
• tensorboard==2.9.0
• wget==3.2

Datasets

We use three datasets; movielens(1m and 10m), amazon grocery, and yelp. Movielens dataset are automatically downloaded if you run an experiment on movielens. Preprocessed amazon grocery data is already in Data folder. Original amazon data can be downloaded from https://jmcauley.ucsd.edu/data/amazon/. For yelp and amazon sports dataset, you need to unzip each rating file with the same name. Original yelp data can be downloaded from https://www.yelp.com/dataset/documentation/main.

Code Structures

"models" folder : This folder includes baseline models(Bert4rec, Narm, Sasrec, Gru4rec) with meta learning setting and adaptive loss networks
"dataloader" file : This file contains data preprocessing and task generation for meta learner
"main.py" file : Main Code. MELO and MAML with sequential recommenders can be trained using this amin file.
"inner_loop_optimizers.py" file : This code is same as inner loop optimizer for MAML++.
"options.py" : Configuration file
"train_original.py" : This code is used for training baseline models. With --save_pretrained option, you can save embedding and model parameters and use these parameters for training meta models.

Running an experiment

Please read options.py carefully to adjust configurations

MELO

• Train MELO(BERT4REC baseline) on Amazon dataset

python main.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --val_size=1000 --num_test_data=5000 --num_train_iterations=3000 --load_pretrained_embedding=True 

• Test MELO on Amazon with best step of n(e.g. 1750)

python main.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --val_size=1000 --num_test_data=5000 --num_train_iterations=3000 --load_pretrained_embedding=True --test --checkpoint_step=1750

MAML

• Train MAML(BERT4REC baseline) on Amazon dataset

python main.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --val_size=1000 --num_test_data=5000 --num_train_iterations=3000 --load_pretrained_embedding=True --use_adaptive_loss=False

• Test MAML on Amazon with best step of n(e.g. 1750)

python main.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --val_size=1000 --num_test_data=5000 --num_train_iterations=3000 --load_pretrained_embedding=True --use_adaptive_loss=False 

Basic Model (without meta learning)

• Train BERT4REC on Amazon dataset

python train_original.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --pretrain_epochs=40 --val_size=1000 --num_test_data=5000 --save_pretrained=False

• Test BERT4REC on Amazon with best step of n(e.g. 22)

python train_original.py --model=bert4rec --mode=amazon --data_path=./Data/amazon/grocery_ratings.csv --val_size=1000 --num_test_data=5000 --save_pretrained=False --test --checkpoint_step=22