Stefan J. Boddie

A transaction log analysis of a digital library

Abstract.As experimental digital library testbeds gain wider acceptance and develop significant user bases, it becomes important to investigate the ways in which users interact with the systems in practice. Transaction logs are one source of usage information, and the information on user behavior can be culled from them both automatically (through calculation of summary statistics) and manually (by examining query strings for semantic clues on search motivations and searching strategy). We have conducted a transaction log analysis on user activity in the Computer Science Technical Reports Collection of the New Zealand Digital Library, and report insights gained and identify resulting search interface design issues. Specifically, we present the user demographics available with our library, discuss the use of operators and search options in queries, and examine patterns in query construction and refinement. We also describe common mistakes in searching, and examine the distribution of query terms appearing in the logs.

Power to the people: end-user building of digital library collections

Naturally, digital library systems focus principally on the reader: th e consumer of the material that constitutes the library. In contrast, this paper describes an interface that makes it easy for people to build their own library collections. Collections may be built and served locally from the users own web server, or (given appropriate permissions) remotely on a shared digital library host. End users can easily build new collections styled after existing ones from material on the Web or from their local files-or both, and collections can be updated and new ones brought on-line at any time. The interface, which is intended for non-professional end users, is modeled after widely used commercial software installation packages. Lest one quail at the prospect of end users building their own collections on a shared system, we also describe an interface for the administrative user who is responsible for maintaining a digital library installation.

A distributed digital library architecture incorporating different index styles

The New Zealand Digital Library offers several collections of information over the World Wide Web. Although full-text indexing is the primary access mechanism, musical collections can also be accessed through a novel melody retrieval system. In offering this service over a three-year period, we have had to face many practical challenges in building, maintaining and administering diverse collections of different kinds of information, involving different search and retrieval systems, with different user interfaces. This paper describes the design of the software we have built to support the service. Interface server programs provide a uniform interface between the search engine and the client, irrespective of the nature of the collection. Search engines that embody completely different index styles operate under a single distributed framework-we describe as examples MG (Managing Gigabytes), a full-text retrieval system, and the MR (Melody Retrieval) system. A flexible protocol for communicating between an interface server and a search engine is defined. The resulting architecture simplifies library administration and the creation of new collections by providing a unified framework under which vastly different user interfaces and search engines can co-exist in a distributed computing environment.

Greenstone: Open source digital library software with end-user collection building

The Greenstone digital library software is an open‐source system for the construction and presentation of information collections. Collections built with Greenstone offer effective full‐text searching and metadata‐based browsing facilities that are attractive and easy to use. Moreover, they are easily maintainable and can be augmented and rebuilt entirely automatically. The system is extensible: software “plugins” accommodate different document and metadata types. Greenstone incorporates an interface that makes it easy for people to create their own library collections. Collections may be built and served locally from the user’s own Web server, or (given appropriate permissions) remotely on a shared digital library host. End users can easily build new collections styled after existing ones from material on the Web or from their local files (or both), and collections can be updated and new ones brought online at any time.

Greenstone: Open-source DL software

Browsing involves hierarchical lists that the user can examine interactively. Metadata (based round the Dublin Core) is the raw material for browsing, and must be provided explicitly or be derivable automatically from the source documents. Different collections offer different searching and browsing facilities. Indexes for both are constructed during a “building” process, according to information in a collection configuration file.

Stress-testing general purpose digital library software

DSpace, Fedora, and Greenstone are three widely used open source digital library systems. In this paper we report on scalability tests performed on these tools by ourselves and others. These range from repositories populated with synthetically produced data to real world deployment with content measured in millions of items. A case study is presented that details how one of the systems performed when used to produce fully-searchable newspaper collections containing in excess of 20 GB of raw text (2 billion words, with 60 million unique terms), 50 GB of metadata, and 570 GB of images.