MIDAS, IIIT Delhi, New Delhi, India.
Cluster Innovation Centre, University of Delhi, New Delhi, India.
J Am Med Inform Assoc. 2021 Jul 14;28(7):1497-1506. doi: 10.1093/jamia/ocab031.
The prevalence of social media for sharing personal thoughts makes it a viable platform for the assessment of suicide risk. However, deep learning models are not able to capture the diverse nature of linguistic choices and temporal patterns that can be exhibited by a suicidal user on social media and end up overfitting on specific cues that are not generally applicable. We propose Adversarial Suicide assessment Hierarchical Attention (ASHA), a hierarchical attention model that employs adversarial learning for improving the generalization ability of the model.
We assess the suicide risk of a social media user across 5 levels of increasing severity of risk. ASHA leverages a transformer-based architecture to learn the semantic nature of social media posts and a temporal attention-based long short-term memory architecture for the sequential modeling of a user's historical posts. We dynamically generate adversarial examples by adding perturbations to actual examples that can simulate the stochasticity in historical posts, thereby making the model robust.
Through extensive experiments, we establish the face-value of ASHA and show that it significantly outperforms existing baselines, with the F1 score of 64%. This is a 2% and a 4% increase over the ContextBERT and ContextCNN baselines, respectively. Finally, we discuss the practical applicability and ethical aspects of our work pertaining to ASHA, as a human-in-the-loop framework.
Adversarial samples can be helpful in capturing the diverse nature of suicidal ideation. Through ASHA, we hope to form a component in a larger human-in-the-loop infrastructure for suicide risk assessment on social media.
社交媒体分享个人想法的流行使其成为评估自杀风险的可行平台。然而,深度学习模型无法捕捉到社交媒体上自杀用户表现出的语言选择和时间模式的多样性,最终会过度拟合特定的线索,而这些线索并不具有普遍适用性。我们提出了对抗性自杀评估分层注意(ASHA),这是一种分层注意模型,它利用对抗学习来提高模型的泛化能力。
我们评估社交媒体用户在 5 个风险严重程度递增的级别上的自杀风险。ASHA 利用基于转换器的架构来学习社交媒体帖子的语义性质,以及基于时间注意的长短期记忆架构来对用户历史帖子进行顺序建模。我们通过向实际示例添加扰动来动态生成对抗性示例,从而可以模拟历史帖子中的随机性,从而使模型具有鲁棒性。
通过广泛的实验,我们确立了 ASHA 的有效性,并表明它明显优于现有基线,F1 得分为 64%。这分别比 ContextBERT 和 ContextCNN 基线提高了 2%和 4%。最后,我们讨论了 ASHA 作为一个人机交互框架在实际适用性和伦理方面的工作。
对抗性样本有助于捕捉自杀意念的多样性。通过 ASHA,我们希望在社交媒体上的自杀风险评估的更大的人机交互基础设施中形成一个组成部分。