The measurement of use of web-based information resources: An early look at vendor-supplied data

To manage Web-based resources effectively, librarians need to evaluate vend or-supplied data about their use. This article explores the types of data a vailable, using as its starting point the elements defined by the Internati onal Coalition of Library Consortia's (ICOLC) "Guidelines for Statistical M easures of Usage of Web-based Indexed, Abstracted, and Full-text Resources. " It discusses the problems and issues of comparing use data from different vendors. Then, illustrated with data from one library, the article address es five measures that have implications for collection management: variabil ity of ICOLC data elements over time, which demonstrated the need to examin e data continually; ratios of queries per session, which showed more stabil ity over time than individual ICOLC elements; use by hour, which documented remote use but confirmed that most use occurred during regular library hou rs; use of electronic journal collections, which was more scattered than th e classic 80/20 distribution; and use of Web-based resources in relation to a disciplinary population, which provided an index of value for assessing use of a particular resource. This study identifies aspects of data collect ion that librarians need to pay special attention to, recommends that vendo rs report the maximum number of simultaneous users per day and data gaps in addition to ICOLC elements, and suggests per capita use as a comparative m easure among libraries.