Concepts of Scaling from the Map Reader's Point of View

Abstract

Map reading is effective to the extent that the user has a basic understanding of the nature of geographical information, is familiar with the logic of various cartographic techniques, and grasps the map deciphering problems that may result through the matching of cartographic method to geographical data in specific mapping situations. The qualitative/quantitative dichotomy that was formerly so frequently resorted to when dealing with geographical information has been replaced by a more sensitive four-level measurement scheme or scaling system which is not only useful in sorting out the relations between environmental information and its cartographic portrayal, but which also provides an important key to understanding the special interpretative considerations that these relations create for the map reader. From a measurement perspective, the information yielded by a particular map symbol depends on the nature of the data that go into its construction, the nature of the data that survive the symbolic transformation, and the ability of the map user to decode the symbol effectively. The utility of measurement concepts in map reading is further demonstrated in the clarifying effect they can have in determining map information content and in the area of map generalization.