Crossing the Border: Subject search across library catalogues — attempting to match subject descriptions by a quantitative method

This article is a preliminary attempt to discuss and construct an experimental library user interface, connecting different libraries in such a way that each library can search other library catalogues using its own classification codes. The second focus of the article is to develop a viable method to locate specific subject clusters in a library catalogue. The classification codes need not be uniform, and the user interface allows for natural language searching. The technique used is the construction of a concordance table between different library catalogues' subject codes on the bibliographic level, enabling the system to determine relative links between different subject codes. The concordance is established on the basis of shared titles.