☆ We thank JonathanHill, Katherine Grooms, and Sebas research assistance. We thank Maria Teresa Garrido, Luis their cooperation for this project. We also thank Alberto A Stefano DellaVigna, Edward Glaeser, Michael Greenstone, Kuhn, Shelly Lundberg, Sendhil Mullainathan, Matt Nei Heather Royer, Reed Walker and Heidi Williams for thei the participants at the NBER Summer Institute Environm our edi...

Many conventional digital library systems offer access to their collections only via full text or meta-data search, or by browsingaccess via a hierarchy of categories. With the increasing amount of digital content available, alternative methods to access the content seem necessary. The SOMLib system, which is based on using Self-Organizing Maps (SOMs), has been used to automatically organize do...

Mobile information systems need to collaborate with each other to provide seamless information access to the user. Information about the user and their context provides the points of contact between the systems. Location is the most basic user context. TIP is a mobile tourist information system that provides locationbased access to documents in the digital library Greenstone. This paper identif...

Josh Angrist, Janet Currie, Carlos Dobkin, Randall Ellis, Michael Greenstone, Rick Hornbeck, David Lee, Doug Miller, Roberto Rigobon, Jon Skinner, Tom Stoker, and Tavneet Suri provided helpful comments and discussions. We also thank Jan Morgan of the California Healthcare Information Resource Center for helpful advice and discussions, Nicole Radmore for help with the National Hospital Discharge...

This article explores the role visual browsing can play within a digital music library. The context to the work is provided through a review of related techniques drawn from the fields of digital libraries and human computer interaction. Implemented within the open source digital library toolkit Greenstone, a prototype system is described that combines images located through textual metadata wi...

Pillow lava rims from the Mesoarchean Barberton Greenstone Belt in South Africa contain micrometer-scale mineralized tubes that provide evidence of submarine microbial activity during the early history of Earth. The tubes formed during microbial etching of glass along fractures, as seen in pillow lavas from recent oceanic crust. The margins of the tubes contain organic carbon, and many of the p...

For digital libraries to remain relevant in the new millennium where the ability to manage knowledge is critical, this paper explores how digital libraries could strategically be evolved into knowledge portals to encapsulate knowledge creation, management, sharing and reusability, features evidently lacking in most conventional digital libraries. Two digital library scenarios of use in educatio...

Thesaurus have been widely used to provide structured vocabularies to describe books, however, they only provide part of the required knowledge for semantic web contexts. This paper proposes the use of ontologies and standard metadata to model semantic descriptions of image collections that refers to book covers. Ontologies represent keyword-based organizations. The classes and the hierarchical...