Geographic Information Systems for the People

Geographic Information Systems (GIS) are tools to input, store, manipulate, query, analyze, and output data that have spatial attributes associated with them. In previous generations, these tasks were accomplished by cartographers who developed the skill sets to represent information from a three-dimensional (at least) world in two dimensions. The development of maps to represent the real world is both art and science and the art involves both aesthetic and crucial decision making about how to accurately convey information. The appearance of computerized systems dedicated to representing data with spatial attributes came to the fore more than two decades ago and as both Caley et al¹. and Mills and Curtis² point out in their articles; it remained initially the provenance of specialists (primarily academics especially in the field of geography) for a substantial period. Although the potential for myriad applications was recognized, the challenge of understanding the details of cartography, geography, data base relations, and computer programming, as well as the specific applications were daunting for nearly everyone.

The parallel developments of improved computer power, programming improvements, and the Internet for data transfer have driven the creation of more usable GIS that could finally begin to meet the intentions of many early pioneering users of making the information available to nearly everyone. Early large-scale applications, such as the Long Island Breast Cancer Study sponsored by the National Cancer Institute, incorporated GIS as part of the information communication program for the public (see www.healthgis-li.com/links/Interpreting_Maps.jsp). The lessons learned from these experiences and reiterated in the current studies help call to mind the challenges as well as the power that GIS provides in communicating information to the people who need it. The ability to represent reams of information that that either could only be presented as summary statistics or compiled into unfathomable tables can be easily presented in a picture (map) for an area of interest. The papers in the present issue provide us with clear evidence of just how far we have come in communicating with the public and engaging them in health-related decisions.

With that power comes a tremendous challenge that Mills and Curtis emphasize in the need for the expert identification of risk and the need for specialists to generate the tools and information for the community to evaluate. This represents a challenge that has been recognized for some time. It was evident as computerized GIS became simple enough that researchers with little or no expertise began to apply it to their research questions. The implications for risk communication with the ecological fallacy looming large have been of concern for a very long time. In addition to the many factors that public health practitioners are familiar with in creating a useful and accurate message, several other issues that are relatively unique to GIS are illustrated by the authors.– These papers provide excellent examples of avoiding those pitfalls.

Although a bit dated, Mark Monmonier's essay, "How to Lie with Maps" remains a classic that individuals leading an exercise with the public should read and take to heart. We strongly encourage it for all our students learning GIS and spatial statistics. It is not necessarily for the general public, although it can easily be read by nearly anyone; however, for someone leading an exercise it is absolutely key toward aiding community planning bodies and helping to minimize either intended or unintended problems with data that can produce substantive issues that affect policy.

Both Caley et al. and Mills and Curtis note the need for retaining specialists, as well as the tremendous interplay and feedback between them and the user community. The success of programs is driven by this because the application of GIS is end-user sensitive. This issue is not only critical to success but also underlies the huge challenge in moving this technology to the appropriate end users. It also returns to the double-edged sword represented by (for most of us) our ignorance about the basic issues of generating maps (in GIS parlance, these are "data layers"), as well as the utility and challenge of using...