Linguistic Generalizations over Descriptions

LFG encodes linguistic generalizations not in terms of formal relations in a type hierarchy, but in terms of relations between descriptions of structures. An LFG functional description -- a collection of equations -- can be given a name, and this name can be used to stand for those equations in linguistic descriptions. In computational treatments, these named descriptions are generally referred to as templates. The use of templates allows for linguistic generalizations to be captured. Template definitions can refer to other templates; thus, a template hierarchy can be drawn to represent inclusion relations between these named LFG descriptions. Importantly, however, the relation depicted in such a diagram shows only how pieces of descriptions are factored into patterns that recur across the lexicon and does not indicate the formal mode of combination of those pieces.