Parentheses insertion based sentence-level text adversarial attack
摘要
In modern multimedia systems, adversarial text attack is a vital way to expose the vulnerability of deep neural networks and improve their robustness. However, existing methods have some limitations. For example, character-level insertion attacks cause misspelling errors and word-level attacks tend to make limited lexical variations. Although sentence-level attacks can greatly enrich the variety of sentences, they are less effective towards fooling victim models and sometimes lead to the wrong representation. In this paper, we propose the Parentheses Insertion Sentence-level Text Adversarial Attack (PI) algorithm that crafts adversarial texts by filling frequently used parentheses. Specifically, we collect a parentheses set (