No abstract

Adversarial training in recommendation is originated to improve the robustness of recommenders to attack signals and has recently shown promising results to alleviate cold-start recommendation. However, existing methods usually should make a trade-off between model robustness and performance, and the underlying reasons why using adversarial samples for training works has not been sufficiently verified. To address this issue, this paper identifies the key components of existing adversarial training methods and presents a taxonomy that defines these methods using three levels of components for perturbation generation, perturbation incorporation, and model optimization. Based on this taxonomy, different variants of existing methods are created, and a comparative study is conducted to verify the influence of each component in cold-start recommendation. Experimental results on two benchmarking datasets show that existing state-of-the-art algorithms can be further improved by a proper pairing of the key components as listed in the taxonomy. Moreover, using case studies and visualization, the influence of the content information of items on cold-start recommendation has been analyzed, and the explanations for the working mechanism of different components as proposed in the taxonomy have been offered. These verify the effectiveness of the proposed taxonomy as a design paradigm for adversarial training.

No abstract

Adversarial training is originated in image classification to address the problem of adversarial attacks, where an invisible perturbation in an image leads to a significant change in model decision. It recently has been observed to be effective in alleviating the long-tailed classification problem, where an imbalanced size of classes makes the model has much lower performance on small classes. However, existing methods typically focus on the methods to generate perturbations for data, while the contributions of different perturbations to long-tailed classification have not been well analyzed. To this end, this paper presents an investigation on the perturbation generation and incorporation components of existing adversarial training methods and proposes a taxonomy that defines these methods using three levels of components, in terms of information, methodology, and optimization. This taxonomy may serve as a design paradigm where an adversarial training algorithm can be created by combining different components in the taxonomy. A comparative study is conducted to verify the influence of each component in long-tailed classification. Experimental results on two benchmarking datasets show that a combination of statistical perturbations and hybrid optimization achieves a promising performance, and the gradientbased method typically improves the performance of both the head and tail classes. More importantly, it is verified that a reasonable combination of the components in our taxonomy may create an algorithm that outperforms the state-of-the-art. CCS CONCEPTS• Computing methodologies → Machine learning approaches.