Given the vast and still growing availability of electronic documents from
around the world, it is becoming increasingly important for managers of the
information systems on which these documents are stored to sort or tag the
se documents so that their end users can most readily access those document
s that are of most interest and use to them, which in our context means in
a language they can understand. Linguini is a vector-space-based categorize
r tailored for high-precision language identification. This paper determine
s the functional dependencies of Linguini's performance and demonstrates th
at it can identify the language of documents as short as 5 to 10 percent of
the size of average Web documents with 100 percent accuracy. It also descr
ibes how to determine if a document is in two or more languages, without in
curring any appreciable extra computational overhead. This approach can be
applied equally to subject-categorization systems to distinguish between ca
ses where, when the system recommends two or more categories, the document
belongs strongly to all or really to none.