The challenge of design for spatial information systems reflects many of the design issues that are seen in the information systems discipline as a whole, as well as the related disciplines of engineering and computer science. A key influence on design in information systems is the work of Herbert Simon, whose concepts influence the development of many aspects of design science theory and the disciplines that contribute to spatial informatics. Simon argued that design sciences for artificial, or created, systems would find their substance in the generation of artifacts (Simon, 1996) that are attempts to meet the purposes of the designers. These artifacts, such as information system software elements, are synthesized from various contributing areas and typically emulate natural systems in some way. In spatial information sys- tems such as geographic information systems (GIS), an example of a natural system is found in the high-level view of a terrain as obtained from an aircraft or satellite.
This emulation can be supplemented with multiple dimensions of quantitative data from other sources such as geometric projection systems, which are combined into the artifact of the GIS software element. In this model, the GIS exemplifies com- puter systems that are designed to emulate human activities, particularly thought processes (Freeman & Hart, 2004).
The view that such artifacts should be a central focus of effort, both in theory and in practice, in information systems research has gained considerable attention (Orlikowski & Iacono, 2001). The design science approach to information systems research “seeks to extend the boundaries of human and organizational capabilities by creating new and innovative artifacts” such as information systems applica- tions implemented in computer software (Hevner, March, Park, & Ram, 2004). In information system design research, increased understanding of the problem area
is expected to result from the activities of building the artifact itself (Vaishnavi &
Kuechler, 2004)
Simon and others maintain that the development of such artifact-based systems will be most efficient if the developers follow a pattern of several general classes of activ- ity. The first of these activities is creating design alternatives and representing these alternatives by means of appropriate representational models. The spatial systems specialty within the field of information systems has developed a variety of such models, many of which are discussed in the following chapters. Next, a series of solution approaches are generated followed by assessment of usability and human factors such as interface design. Finally, the actual artifacts are developed, usually in the form of a series of prototypes, which in turn are evaluated. Many variants of this iterative process are familiar within design-based disciplines (NSF, 2004).
The task of designing spatial systems presents special opportunities to emulate natural systems by allowing visual and cognitive ordering of information to enhance its communication power. Such information visualization tools allow the user to examine the “terrain” of information (Bederson, 2001; Shneiderman, Card, Norman, Tremaine, & Waldrop, 2001). The analytical potential of information visualization methods is important in any context where a large body of data forms the basis for decision-making. In particular, visualization tools have special relevance in situations in which the decision maker faces information overload and hidden or ambiguous patterns in the decision-basis information, such as what one might face in the following situations.
For example, spatial information system artifacts can enable pattern discovery through visual inspection that can be superior to other, non-spatial information sys- tem methods (Gershon, Eick, & Card, 1998). Pattern discovery through interactive techniques as provided in spatial information systems can augment the information search process in unexpected ways (Kreuseler & Schumann, 1999). In addition, the visualization of spatial information can allow users to intelligently develop specific questions to be asked via more traditional mechanisms, such as search engines (Shneiderman, 1999).
The unique opportunity for a spatial information system to emulate and extend natural human processes places it in a special position to develop as an important specialty within the information systems field, as well as to contribute to the body of work in information system design theory.
Information.System.Design.Theory
As presented by Walls, Widmeyer, and El Sawy, 1992), the concern of researchers in the Information Systems discipline is the design of systems and the development of system design theories that address the question of how to establish relation-
ships between components of a system to achieve a specific result. An information system design theory (ISDT), then, refers to an integrated prescription consisting of a particular class of user requirements, a type of system solution (with distinc- tive features), and a set of effective development practices (Markus et al., 2002).
Here, Walls et al. refer to meta-requirements (user requirements), which describe the specific goals that are applicable to any system of the type to which the theory relates. Meta-design (system solution) describes the specific artifacts that are ap- plicable to the meta-requirements, while the design method (effective development practices) describes the procedures to be utilized in building a system of the type to which the theory relates. Underlying these three features (meta-requirements, meta- design, design method) of an ISDT are kernel theories (an academic theory and/or a practitioner theory-in-use) that enable the formulation of empirically-testable hypotheses relating the design theory to expected outcomes. The ISDT addresses both the product of the design effort, which is typically an artifact or instantiation, and the process of design. In this way, the method of design can be adapted to the meta-requirements of the product. These design theory characteristics help to establish why the application of one particular ISDT to a specific situation yields better results than the application of a different ISDT. For example, “it should be possible to establish empirically that the application of Decision Support System design theory to a particular set of requirements produces better results than applying Transaction Processing System design theory to the same requirements” (Markus et
Figure 1. Components of an information system design theory
Kernel Theores
Kernel Theores
Meta- Requrements
Meta- Desgn
TestableDesgn Product Hypothess
Desgn Method
TestableDesgn Process Hypothess Design Product Design Process
al., 2002, p. 181). Figure 1 illustrates the relationships between the components of an ISDT where the meta-requirements and meta-design form the core of the design product, while the design method forms the core of the design process.