GEOGRAPHIC METHODS & POLICY: Using Geographic Information Systems to Inform Education Policy
Cobb, Casey D., Educational Research Quarterly
When maps are used in conjunction with relational databases they provide a geographical (and visual) context with which to describe and analyze information. This unique combination of map and database comprises what is called a geographic information system, or GIS. This article describes ways in which geographical methods can be used to inform educational policy and practice. Several examples are presented that illustrate the application of GIS in education research. Education researchers, policy analyst and planners are beginning to realize the benefits of investigating issues from a geographic perspective.
The personal computer has made a complex technology that was once limited to cartographers and geographers readily available to researchers in the social sciences. Education researchers, policy analysts and planners are beginning to realize the benefits of investigating issues from a geographic perspective. This article describes ways in which geographical methods can be used to inform educational policy and practice.
Geographic Information Systems: More than Maps
By themselves, maps provide an assortment of geographic information. Indeed, they are the fundamental tools of geographers. But maps can also be used as a basis for more sophisticated spatial analyses. For example, when maps are used in conjunction with relational databases they provide a geographical (and visual) context with which to describe and analyze information. This unique combination of map and database comprises what is called a geographic information system, or GIS.
Understandably, a GIS is sometimes confused with a GPS, or "global positioning system." Although they do share integral features, a GPS involves satellite technology to orient people and objects on earth, whereas a GIS has more to do with the analysis of map information. More specifically, a GIS is a computer-based technology that allows one to create, store, see and manipulate geographically referenced information (Institute, 2000). Much like other database software programs, but unlike computer-aided design systems, a GIS can perform queries and statistical analyses on spreadsheet-formatted data. The combination of geographical and statistical analysis presented in graphical format makes the use of this technology uniquely powerful.
Digital maps are produced by a GIS. These maps present features in the form of either points, lines or polygons. Examples of common features include streets and highways (line features), schools (a point feature) and census tract boundaries (a polygon feature). Since the maps are created by and viewed on a computer, it is easy to turn these features on and off, and to view them in various combinations.
One of the most potent and distinctive aspects of a GIS is that map features can be linked to relational databases. Simply by moving the cursor over an area or point of interest and clicking the mouse, a new window appears supplying a wealth of information regarding that map element. The information can take the form of anything from summary statistics to a picture to even a video clip:
Through a function known as visualization, a GIS can be used to produce images - not just maps, but drawings, animations, and other cartographic products. These images allow researchers to view their subjects in ways that literally never have been seen before. The images often are equally helpful in conveying the technical concepts of GIS study subjects to non-scientists. (Garson & Biggs, 1992, p. x)
This characteristic of a GIS is analogous to the hyperlink technology that pervades other electronic media. But beyond this hyperlink capability, a GIS provides the medium to engage in what is called "analytic mapping." First used in the early 1960s, analytic mapping is a blend of cartography and geographic analysis. It is a process that occurs within (and with the use of) a GIS. Analytic mapping permits various sophisticated "geo-statistical analyses" such as areal averaging and centroid computation, and thus provides researchers with statistical alternatives to conventional multivariate statistics (Garson & Biggs, 1992). …