DANSK DS/ISO 24610-2 PDF

This international standard provides a format to represent, store or exchange feature structures in natural language applications, for both annotation and production of linguistic data. It is ultimately designed to provide a computer format to define a type hierarchy and to declare the constraints that bear on a set of feature specifications and operations on feature structures, thus offering means to check the conformance of each feature structure with regards to a reference specification. Feature structures are an essential part of many linguistic formalisms as well as an underlying mechanism for representing the information consumed or produced by and for language engineering applications. A Feature System Declaration (FSD) is an auxiliary file used in conjunction with a certain type of text that makes use of fs (that is, feature structure) elements. The FSD serves three purposes: - It provides an encoding by which types and their subtyping and inheritance relationships can be introduced and defined, thus laying the basis for constructing a feature system. - It provides a mechanism by which type constraints can be declared, against which typed feature structures are validated. These constraints specify the features associated with some specific types and the range of admissible values for those features, as well as other parochial restrictions drawn from the empirical domain being modelled. - It provides a mechanism that can induce the intended interpretation of underspecified feature structures by installing default values for missing features and their values. The scheme described in this standard (part 2) may be used to document any feature system, but is primarily intended for use with the typed feature structure representation defined in part 1 of ISO 24610-1:2006 (E). The feature structure representations of part 1 specify data structures that are subject to the typing conventions and constraints specified using part 2. The feature structure representations of part 1 are also used within some of the elements defined in part 2.