PRINCIPLES OF GEOGRAPHIC INFORMATION SYSTEMS

THIS TEXT IS A COMPLETELY REVISED VERSION OF "PRINCIPLES OF GEOGRAPHICAL INFORMATION SYSTEMS FOR LAND RESOURCES ASSESSMENT" WHICH WAS FIRST PUBLISHED IN 1986. GIS ARE NOT JUST USED FOR ELECTRONIC MAP-MAKING BUT TODAY ARE MAJOR TOOLS FOR THE MANAGEMENT OF OUR PHYSICAL AND SOCIAL ENVIRONMENT. GIS ARE USED TO ASSIST POLITICAL DECISIONS AND PLAY A PART IN MARKET RESEARCH, IN THE MANAGEMENT OF UTILITY SERVICES, IN AUTOMATED NAVIGATION SYSTEMS AND IN MANY OTHER FIELDS. THIS BOOK PRESENTS A THEORETICAL BASIS FOR GIS, WHICH IS OFTEN LACKING IN OTHER TEXTS. SPATIAL DATA ARE USUALLY BASED ON TWO, DICHOTOMOUS PARADIGMS, EXACTLY DEFINED ENTITIES IN SPACE, SUCH AS LAND PARCELS, OR THE CONTINUOUS VARIATION OF SINGLE ATTRIBUTES, SUCH AS TEMPERATURE OR RAINFALL. METHODS FOR MODELLING BOTH KINDS OF PHENOMENA AND STORING THEM IN SPATIAL DATABASES ARE DESCRIBED IN DETAIL, INCLUDING THE USE OF GEOSTATISTICS FOR INTERPOLATING FROM POINTS TO CONTINUOUS FIELDS. EXAMPLES OF HOW SPATIAL DATA AND AN ANALYSIS OF