Measuring public library accessibility: A case study using GIS

Physical accessibility is considered a fundamental measure of freedom to attend activities. Although several accessibility analyses have been conducted of public libraries, these studies tend to measure the distance from the users' homes to the library using straight lines. This generally serves as a poor measurement of actual travel distances. In order to provide more realistic analysis, and measure patterns of library access more accurately, this study employed geographic information systems (GIS), including descriptive and statistical analyses, and a road network-based distance measure. One finding from the GIS analyses was that distance was a determining factor for library use. Specifically, the evidence shows that distance affected a considerable number of registered users who lived within the areas that were defined through Thiessen polygons. Another finding was that there was a difference in the travel distance between ethnic groups: Caucasians went further to access public libraries than other ethnic groups. Finally, in terms of the relationship between distance and demographic data, household characteristics relative to children and education level were significantly related to the travel distance of users. To improve the accessibility of public libraries, this study recommends librarians define service areas for libraries, develop library programs and services for susceptible user groups, and evaluate user groups' needs.

► Travel distance is critical in assessing accessibility of libraries for users.
► Road networks rather than straight lines give an accurate measure of travel distance.
► A Thiessen polygon analysis renders a library service area map based on distance.
► Library registration and circulation data are used to analyze use patterns.