论文标题
利用对比度学习和数值证据使法律判断预测混淆
Exploiting Contrastive Learning and Numerical Evidence for Confusing Legal Judgment Prediction
论文作者
论文摘要
鉴于法律案件的事实说明文本,法律判决预测(LJP)旨在预测案件的指控,法律文章和罚款条款。 LJP的核心问题是如何区分令人困惑的法律案件,而仅存在细微的文本差异。先前的研究未能通过标准的跨膜分类损失来区分不同的分类误差,并且忽略了事实描述中预测惩罚期限的数字。为了解决这些问题,在这项工作中,我们提出了一个基于MOCO的监督对比学习,以学习可区分的表示形式,并探索最佳策略来构建积极的示例对,以同时使LJP的所有三个子任务受益。其次,为了利用法律案件中的数字来预测某些案件的罚款条款,我们进一步增强了由提取的犯罪金额的事实描述的表示,这些犯罪金额由预训练的算术模型编码。对公共基准测试的广泛实验表明,所提出的方法实现了新的最新结果,尤其是在使法律案件混淆的情况下。消融研究还证明了每个组件的有效性。
Given the fact description text of a legal case, legal judgment prediction (LJP) aims to predict the case's charge, law article and penalty term. A core problem of LJP is how to distinguish confusing legal cases, where only subtle text differences exist. Previous studies fail to distinguish different classification errors with a standard cross-entropy classification loss, and ignore the numbers in the fact description for predicting the term of penalty. To tackle these issues, in this work, first, we propose a moco-based supervised contrastive learning to learn distinguishable representations, and explore the best strategy to construct positive example pairs to benefit all three subtasks of LJP simultaneously. Second, in order to exploit the numbers in legal cases for predicting the penalty terms of certain cases, we further enhance the representation of the fact description with extracted crime amounts which are encoded by a pre-trained numeracy model. Extensive experiments on public benchmarks show that the proposed method achieves new state-of-the-art results, especially on confusing legal cases. Ablation studies also demonstrate the effectiveness of each component.