Total Error Estimation in a Spatial Database for GIS : Spatial Accuracy Assessment in Natural Resources and Environmental Sciences/ Second International Symposium : Spatial Accuracy Assesment in Natural Resources and Environmental Sciences/Second International Symposium

1996

S. 501-507

13 Lit. Ang.

Unselbständiges Werk

200047483

The aim of this paper is to present a methodology to estimate the errors in digital spatial database originated from the digitizing a large number of maps. It is undestood that the desired quality of that digital database is associated to a specific foreseen use. Supposing that the spatial database is the population to be sampled and the objects on it as the primary sampling units, two strategies are discussed: the spatial, focused on areas where errors are likely to occur and the non-spatial sampling, focused on the selection of objects according to a database structure. The errors types are organized in a sequential structure upon which a multi-stage sampling strategy is applied. The sampling areas are selected by a specific sampling frame, quadrats, selected according to spatial variability evaluated by entropy measures. Supposing that the amount of errors in the spatial units have a Poisson distribution, the total error distribution can be estimated, allowing thus the inference of the whole population quality.