Georeferencing: The geographic associations of information

This text offers a cogent introduction to the concepts, history, and future directions of incorporating geographic information into a wide range of topics and disciplines. It offers readers a quick introduction to core geographical concepts in the digital age. Linda Hill is an early pioneer in the translation of traditional geographic artifacts into new digital media formats, and her long-term experience with the topic creates an accessible and timely text. The introduction begins by defining georeferencing as “relating information to geographic location” (p. 1). The reality of implementing this is quite complex and Hill draws on a variety of disciplines to do so, including geography, library sciences, and even psychology. The first step in georeferencing involves differentiating between informal and formal ways of referencing locations. Informal means are commonly used in everyday speech and include the use of place-names such as towns and landmarks. Formal means use spatial referencing systems like longitude and latitude coordinates. The troubled relationship between these two schemes become clear when we attempt to assign coordinates to place-names. Should a town be represented by its central coordinate? If so, what analytical tools should we use to determine this central position? The complications continue in regard to accessing information based on geographic location. This includes retrieving records from databases based on geographic coordinates or placenames. The intersection of these ideas lies at the heart of Hill’s thesis that “the users of information systems are best served through unified georeferencing where both placename and geospatial access works across all types of information resources” (p. 8). In other words, the best practice for delivering georeferenced material is to cast the widest net possible in terms of associating it with spatial coordinate and place-names. The text builds on this assertion and provides the reader with a working historical knowledge of the conversation across disciplines on this problem. The second chapter looks at spatial cognition and information systems by drawing heavily on cognitive psychology to better understand current thinking on how humans perceive and order geographic space. We tend to understand space based on landmarks and less on geographic coordinates or cardinal directions, and such realizations need to inform the structuring of systems to deliver georeferenced content. Hill’s expertise comes through as she presents a detailed discussion of the actual artifacts dealt with in regards to georeferencing library materials. Such materials include maps, digital map layers, and geospatially referenced images (e.g., aerial photography). The majority of these artifacts are typically managed by specialist librarians, and users retrieve them through one of two ways. First is using geographical coordinates to locate places within the geospatial information objects. These artifacts include maps and satellite images. The second uses placenames through a method called indirect georeferencing. Examples include books and museum specimens that are attached to a place-name. The challenge for providers of such content “is to create systems that support the discovery of information resources relevant to particular locations” (p. 62) using one or both of these methods. The difficulty of reconciling place-names and geographic coordinates remains a central theme throughout the book. The need to attach spatial attributes to collection materials is compounded by certain established traditions. For example, many librarians and historical