Decision-Making with Conflicting Cartographic Information: The Case of Groundwater Vulnerability Maps

Abstract

Conflicting cartographic information can cause problems when used tosupport planning decisions. Creation of conflicting information is becoming more common as geographic visualization and modeling software are used to develop multiple maps that represent different views of the same data. This paper presents groundwater vulnerability mapping as an example of information conflicts of this type. Three different vulnerability models applied to the same test data produced radically different results. This information was presented to a group of local planners to examine how they would deal with the conflicts. Through this exercise it became apparent that each planner used highly individual criteria to evaluate the resuJts from the models. A continuum of strategies describes the range of responses from aspatial to spatial approaches. Jung's theory of psychological types is applied to further understand variation in responses. A venues for further research are suggested in the representation of cartographic information conflicts, the role of psychological types in decision-making with maps, and the role of group dynamics in decision-making with maps.

Water Quality Mapping for Water Management

“…A number of cartographers have deplored the lack of knowledge about the effectiveness of the various forms of cartographic visualization (Unwin et al 1994;MacEachren 1995;Rader and Janke 1998). But, how can we effectively evaluate the effectiveness of a strategy of visualization?…”

“…According to Bishop (1994, p. 64), it is important to continually evaluate each cartographic representation in order to know its legibility according to its use by different people in decision-making. But, as many authors have noted, very little cartographic research has examined maps from this perspective (Unwin et al 1994;Keller 1995;Torguson 1997;Rader and Janke 1998). This type of research, however, appears necessary for proposing representations adapted to the non-specialist (Kitchin 1994).…”