Metadata aggregation and "automated digital libraries"

Abstract

Over three years ago, the Core Integration team of the National Science Digital Library (NSDL) implemented a digital library based on metadata aggregation using Dublin Core and OAI-PMH. The initial expectation was that such low-barrier technologies would be relatively easy to automate and administer. While this architectural choice permitted rapid deployment of a production NSDL, our three years of experience have contradicted our original expectations of easy automation and low people cost. We have learned that alleged "low-barrier" standards are often harder to deploy than expected.In this paper we report on this experience and comment on the general cost, the functionality, and the ultimate effectiveness of this architecture.

The impact of MeSH (Medical Subject Headings) terms on information seeking effectiveness

“…From a practical perspective, the research team at the National Science Digital Library (NSDL) found it difficult to develop structured metadata similar to a library union catalog because of the lack of information professionals with adequate subject domain expertise, computer technical expertise and cataloging experiences (Lagoze, Krafft, Cornwell, Dushay, Eckstrom, & Saylor, 2006). It suggests that the implementation of structured metadata in a distributed environment through metadata aggregation requires enormous amount of well-trained personnel support, even though the specification of metadata standards, such as Dublin Core and OAI-PMH (Open Archives Protocol for Metadata Harvesting), is not considered as complex as LCSH.…”

Representing Contextualized Information in the NSDL

“…This work follows more than three years of work by the NSDL Core Infrastructure (CI) team, and has been described in a number of other papers [14,15]. Stated very briefly, this earlier work used OAI-PMH to populate a metadata repository (MR).…”

“…In particular, our experience has led to two conclusions. First, the technical and organizational infrastructure to support harvesting, aggregation, and refinement of metadata is surprisingly human-intensive and expensive [15]. Second, in a world of increasingly powerful and ubiquitous search engines, digital libraries must distinguish themselves by providing more than simple search and access [16].…”

Metadata for semantic and social applications<br />DC- 2008 Berlin

“…These collection descriptions indicate such things as the purpose of the collection, its subject, the method of selection, size, nature of contents, coverage, completeness, representativeness, and a wide range of summary characteristics, such as statistical features. This information enables collections to function not just as aggregates of individual data items but as independent entities that are in some sense more than the sum of their parts, as intended by their creators and curators (Curral, Moss & Stuart, 2005;Lagoze, et al 2006Palmer, 2004. Collection-level metadata, which represents this information in computer processable form, is thus critical to the distinctive intellectual and cultural role of collections as something more than a set of individual objects.…”

“…Preventing this loss of information is particularly difficult, and particularly important, for "metasearch", where item-level descriptions are retrieved from a number of different collections simultaneously, as is the case in the increasingly distributed search environment of the Internet (Christenson & Tennant, 2005;Dempsey, 2005;DLF, 2005;Lagoze, et al, 2006;Warner, et al, 2007).…”