X-tract: structure extraction from botanical textual descriptions

Most available information today, both from printed books and digital repositories, is in the form of free-format texts. The task of retrieving information from these ever-growing repositories has become a challenge for information retrieval (IR) researchers. In some fields, such as botany and taxonomy, textual descriptions observe a set of rules and use a relatively limited vocabulary. This makes botanical textual descriptions an interesting area to explore IR techniques for finding structure and facilitating semantic analysis. This paper presents X-tract, a solution to the problem of text analysis and structure extraction in a specific application domain, namely floristic morphologic descriptions. The solution demonstrates the potential of using a grammar in the determination of information structure in a botanical digital library. We have developed a prototype based on this approach in which given an HTML or plain text, X-tract analyzes it and presents results to the user so he or she can verify the proposed structure before updating the database. This transformation is useful also in the process of storing morphologic descriptions in a database with a preestablished format. The solution is implemented in the context of the Floristic Digital Library (FDL), a large digital library project comprising a wide variety of botanical documents, formats and services.