Enhancing User Interactions in Digital Libraries

Implementing Faceted Search User Interface

A digital library can be underpinned by a search platform such as Apache Solr, which facilitates faceted search services. In my previous posts, I have described the development of a Solr-based search engine infrastructure, involving metadata and rich binary documents indexing of multi-sourced data, viz., the CERN Library book data, content from a digital repository (Fedora). The search engine only provides underpinning services. It does not provide a user interface.

This post outlines the work involved in prototyping a digital library user interface - UX2 Library. It describes the UX design, development made with respect to an associated open source technology. We have recently tested the prototype with a group of users from the University of Edinburgh and published the results: summary and report. In my next post, I shall propose an agile technique based on 'user stories', to address the usability issues arising from this user study.

For a general introduction to both faceted search and Apache Solr, see "Developing Faceted Search Using Apache Solr, Part 1".

Tech Note: Developing Faceted Search Using Apache Solr, Part 1

Searching and sifting through large amount of information is a challenging task and a norm confronting web users today. There is a need for resource discovery services capable of dealing with large search resultsets effectively. Previous research indicates a tendency for users to prefer interfaces that incorporate some form of categorisation and grouping of results. These types of UIs tend to enhance the efficiency of information seeking and provide greater user satisfaction. This post describes the development of faceted search, a resource discovery approach based on a type of category system which has become prevalent in digital libraries. A remit of the UX2.0 project involves enhancing an existing digital library featuring faceted search through user-centred design (UCD). We are also evaluating AquaBrowser a leading library product facilitating faceted search.

This post relates to my recent work on two systems. It describes the development and setting up of a faceted search infrastructure - Apache Solr for Blacklight, a Ruby-on-Rails and open source resource discovery UI. To provide concentration user experience, the infrastructure provides data aggregated from multiple and heterogeneous sources.

Part 1 of this account (this post) describes the general setup of Solr for multi-sourced data and the experience of importing the CERN book dataset, using the Data Import Hanlder (DIH) of Solr. UX2 is incorporating the book data in combinant with digital library objects, for low-fi content-rich UI prototypes testing.

A forthcoming post (Part 2) describes programmatic development of Solr, to enable indexing of Dublin Core metadata and binary documents in multiple formats (PDF, PowerPoints etc) held in an existing Fedora Commons digital repository.

User Study of AquaBrowser and UX2.0

Resource discovery services for digital library have evolved significantly. There is an increasing use of dynamic user interface. New ways of user interactions are also emerging. Faceted searching for example provides a “navigational metaphor” for boolean search operations. It also results in greater user satisfaction (Olson 2007). AquaBrowser is a leading library product which provides faceted searching and new resource discovery features based on emerging interaction design patterns ('fresh, modern interface' according SerialsSolutions). These features appear to support better ways of searching: fast drill-down of results, enhanced search context.

An interaction design pattern we explored earlier this year, through a UX2.0 study (heuristic inspection) is the "Word Cloud" feature which according to SerialsSolution provides context-sensitive exploration. The unique UI is essentially a composite design pattern based on word (tag) cloud and spatial navigation - a term coined by the Nielsen Norman Group. AquaBrowser's tag cloud is unique as it does not utilise the typical size effect and rely on colours showing different types of word association. It also uses spatial navigation in combinant - tags move or reorganising during user interactions. Despite its popularity, the use of tag cloud even in its most basic form, remains contentious and nascent at least from usability perspectives. A recent statement from the Nielsen Norman Usability Week has urged sites to use tag cloud with caution and certainly not to use it for mainstream purposes. Furthermore this technique may either become a standard design or expire in a few years. On the contrary, recent studies on AquaBrowser have confounded the usual dismissive views of word cloud, suggesting potential for serendipitous discovery even for domain experts (Olson 2007). Moreover, word cloud has been an active subject in digital library research and development, e.g. as a visualisation device to gauge content relevance 'as a glance' (Gottron 2009).