Feature Structure Formalisms: Mathematical And ComputationalFoundations For Linguistic Theory

在过去的几年里，被称为特征结构的数学对象已经被理论和计算语言学中的许多研究传统(统称为基于统一的语法)用于模拟自然语言领域中的广泛现象。主要研究者将探讨这一论点，即特征结构的形式主义经过适当的扩展，能够作为具有确定经验结果的自然语言结构的数学上精确和计算上易于处理的理论的基础。然后，研究者将把这些扩展应用于明确的基于原则的语言学理论的形式化和实际的自然语言程序的构建，集中在诸如语序、约束、远距离依附(A-bar移动)和语篇结构等核心重要的语言现象上。要研究的扩展包括：(1)不同种类的否定约束(经典否定、直觉否定和独立性)；(2)不同种类的类型群(通过逻辑、通过图的结构约束、通过代数模型的排序)和相关的继承方案(包含多态)；(3)列表值、集值等概念的实现(参数多态)；(4)除等式以外的谓词(如不等式、追加、子集、并集)和方程理论的“内建”(广义统一)；(5)递归的引入方法；(6)无限方法(如“函数不确定性”)；(7)动态解释。

In the past several years, the mathematical objects known as feature structures have been employed by numerous research traditions in theoretical and computational linguistics (collectively referred to as "unification-based grammar") for modeling a wide range of phenomena in the domain of natural language. The principal investigator will explore the thesis that the formalism of feature structures, appropriately extended, is capable of serving as the foundation for mathematically precise and computationally tractable theories of natural language structure that have determinate empirical consequences. The researcher would then apply such extensions to the formalization of explicit "principle-based" linguistic theories and to the construction of practical NLP programs, focussing upon such centrally important linguistic phenomena as word order, binding, long-distance dependencies ("A-bar movement"), and discourse structure. Extensions to be investigated include, inter alia, the following: (1) different varieties of negative constraints (classical negation, intuitionistic negation, and apartness); (2) different varieties of type regiments (via the logic, via structural constraints on graphs, via sorting of algebraic models) and associated inheritance schemes (inclusion polymorphism); (3) realization of such notions as list value and set value (parametric polymorphism); (4) predicates other than equality (e.g. inequality, append, subset, union) and "building-in" of equational theories (generalized unification); (5) methods for introducing recursion; (6) infinitary methods (e.g. "functional uncertainty); and (7) dynamic interpretation.