交叉依赖的稀缺性：特定约束的直接结果？
The scarcity of crossing dependencies: a direct outcome of a specific constraint?
摘要：
句子的结构可以表示为一个网络，其中顶点是单词，边表示句法依赖关系。有趣的是，交叉句法依赖在人类语言中并不常见。这就引出了一个问题，即语言中交叉点的缺乏是否源于对交叉点的独立和具体的限制。我们提供的统计证据表明，这是不是这样的，作为一个简单的预测器，基于零假设的本地概率，两个依赖性交叉给定其长度的依赖性交叉的句子从广泛的语言的比例可以准确地估计。这个预测器的相对误差平均不会超过5%，而假设句子中单词的随机排序的基线预测器的误差至少要大6倍。我们的研究结果表明，自然语言中交叉频率低既不是源于隐藏的语言知识，也不是由于交叉本身的不可取性，而只是依赖长度最小化原则的副作用。
英文摘要：
The structure of a sentence can be represented as a network where vertices are words and edges indicate syntactic dependencies. Interestingly, crossing syntactic dependencies have been observed to be infrequent in human languages. This leads to the question of whether the scarcity of crossings in languages arises from an independent and specific constraint on crossings. We provide statistical evidence suggesting that this is not the case, as the proportion of dependency crossings of sentences from a wide range of languages can be accurately estimated by a simple predictor based on a null hypothesis on the local probability that two dependencies cross given their lengths. The relative error of this predictor never exceeds 5% on average, whereas the error of a baseline predictor assuming a random ordering of the words of a sentence is at least 6 times greater. Our results suggest that the low frequency of crossings in natural languages is neither originated by hidden knowledge of language nor by the undesirability of crossings per se, but as a mere side effect of the principle of dependency length minimization.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
