Using XML as a questionnaire specification language

XML (Extensible Markup Language) is an amazingly powerful tool that is widely used for exchanging data files over the Internet and more generally for describing structured documents. This paper describes a novel application of XML to represent the active processing associated with a computer-assisted interview in addition to representing the structure, content, and format of the questionnaire. This is accomplished by creating a set of XML tags that embody a simple functional programming language.