ABSTRACT
This chapter describes the effects of generalisation on the point-in-polygon analysis, and this is followed by the description of the overlay operation that was carried out. A point-in-polygon and an overlay operation were carried out in order to determine how generalisation affected typical Geographical Information Systems (GIS) map manipulations. The point-in-polygon procedure used only road data, in order to investigate a single feature type. The account of the overlay operation is divided into two parts. The first part covers the results of the overlay when only the features common to all map scales were used. The second part describes the results when the overlay was repeated using all of the features present on the different maps. This was to simulate the overall impact of the generalisation process on a typical GIS analysis, and also to evaluate the more probable result that a GIS user would have obtained.
