ROBUREC: Building a Robust Recommender using Autoencoders with Anomaly Detection
Ahmed Aly, Dina Nawara, Rasha Kashef · 2023
In the realm of social network analysis and mining, recommendation systems have become indispensable algorithms in assisting users and industries in navigating the available contents or products in various domains and getting the most personalized recommendations to their interests and preferences. However, if the input data has been generated by malicious users, that poses a significant challenge to recommender systems' reliability and efficiency. One of the main threats that poses a challenge to recommender systems is shilling attacks. Shilling attacks tend to manipulate or poison the data in the systems' training phase, leading to biased or compromised recommendations. To address this challenge, we propose a robust recommender system using variational autoencoders (VAE) with Anomaly detection. Our model learns complex and non-linear patterns by exclusively focusing on the user-item interaction data, represented by a binary user-item interaction matrix, making it more resilient to classic shilling attacks. Moreover, our paper incorporates an anomaly detection mechanism, alongside the autoencoder, that analyzes the reconstruction errors, i.e. (MSE) between the original interactions and their reconstructed ones. We test the model on a real-world dataset and evaluate it using Recall@k and NDCG@k. This work enhances the trustworthiness and accuracy of recommendation algorithms, mainly when deployed in social network analysis and mining, where the potential for malicious data manipulation is a critical concern.