论文标题
神经符号熵正规化
Neuro-Symbolic Entropy Regularization
论文作者
论文摘要
在结构化的预测中,目标是共同预测许多输出变量,这些变量共同编码结构化对象 - 图中的路径,实体关联三重或对象的排序。如此庞大的输出空间使学习艰难,需要大量的标记数据。不同的方法利用替代监督来源。一种方法 - 熵正则化 - 认为决策边界应位于低概率区域。它从未标记的示例中提取监督,但对输出空间的结构仍然不可知。相反,神经符号方法利用并非每个预测都对应于输出空间中的有效结构的知识。但是,他们没有进一步限制学习的产出分布。本文介绍了一个统一这两种方法的框架。我们提出了一个损失,神经符号熵的正则化,这鼓励模型自信地预测有效的对象。它是通过将熵正规化限制为仅在有效结构上的分布来获得的。当输出约束表示为可处理的逻辑电路时,该损失将有效计算。此外,它与其他消除无效预测的神经符号损失无缝集成。我们证明了方法在一系列半监督和完全监督的结构化预测实验中的功效,我们发现它会导致其预测更准确且更有可能有效的模型。
In structured prediction, the goal is to jointly predict many output variables that together encode a structured object -- a path in a graph, an entity-relation triple, or an ordering of objects. Such a large output space makes learning hard and requires vast amounts of labeled data. Different approaches leverage alternate sources of supervision. One approach -- entropy regularization -- posits that decision boundaries should lie in low-probability regions. It extracts supervision from unlabeled examples, but remains agnostic to the structure of the output space. Conversely, neuro-symbolic approaches exploit the knowledge that not every prediction corresponds to a valid structure in the output space. Yet, they does not further restrict the learned output distribution. This paper introduces a framework that unifies both approaches. We propose a loss, neuro-symbolic entropy regularization, that encourages the model to confidently predict a valid object. It is obtained by restricting entropy regularization to the distribution over only valid structures. This loss is efficiently computed when the output constraint is expressed as a tractable logic circuit. Moreover, it seamlessly integrates with other neuro-symbolic losses that eliminate invalid predictions. We demonstrate the efficacy of our approach on a series of semi-supervised and fully-supervised structured-prediction experiments, where we find that it leads to models whose predictions are more accurate and more likely to be valid.