Measurement-based Gis

GIS designs have evolved over the past 30 years, and once adopted a design tends to persist as a legacy despite progress in fundamental research. A feature of most GIS designs is the representation of position by derived coordinates, rather than by original measurements. In such coordinate-based GIS it is impossible to apply traditional error analysis, or to estimate uncertainties in derived products. Thus concern for accuracy issues forces a rethinking of fundamental design. Measurement-based GIS is defined as retaining details of measurements, such that error analysis is possible, and such that corrections to positions can be appropriately propagated through the database. It is shown that measurement-based designs have major economic advantages, in addition to a more comprehensive approach to uncertainty.