Meta-Metadata: An Information Semantic Language and Software Architecture for Collection Visualization Application

Information collection and discovery tasks involve aggregation and manipulation of information resources. An information resource is a location from which a human gathers data to contribute to his/her understanding of something significant. Repositories of information resources include the Google search engine, the ACM Digital Library, Wikipedia, Flickr, and IMDB. Information discovery tasks involve having new ideas in contexts of information collecting. The information one needs to collect is large and diverse and hard to keep track of. The heterogeneity and scale also make difficult writing software to support information collection and discovery tasks. Metadata is a structured means for describing information resources. It forms the basis of digital libraries and search engines. As metadata is often called, "data about data," we define meta-metadata as a formal means for describing metadata as an XML based language. We consider the lifecycle of metadata in information collection and discovery tasks and develop a metametadata architecture which deals with the data structures for representation of metadata inside programs, extraction from information resources, rules for presentation to users, and logic that defines how an application needs to operate on metadata. Semantic actions for an information resource collection are steps taken to generate representative objects, including formation of iconographic image and text surrogates, associated with metadata. The meta-metadata language serves as a layer of abstraction between information resources, power users, and application developers. A power user can enhance an existing collection visualization application by authoring meta-metadata for a new information resource without modifying the application source code. The architecture provides a set of interfaces for semantic actions which different information discovery and visualization applications can implement according to their own custom requirements. Application developers can modify the implementation of these semantic actions to change the behavior of their application, regardless of the information resource. We have used our architecture in combinFormation, an information discovery and collection visualization application and validated it through a user study.