A FRAMEWORK FOR THE VALIDATION OF GLOBAL NIGHTTIME ENVIRONMENTAL PRODUSTS

THE GRIDDED POPULATION OF THE WORLD VERSION 4 (GPW4) DATA COLLECTION WAS CREATED BASED ON OFFICIAL DEMOGRAPHIC INFORMATION FROM THE 2010 ROUND OF GLOBAL CENSUSES. GPW4 POPULATION COUNT DATA ARE GENERATED ON THE BASIS OF A UNIFORM AREAL DISTRIBUTION METHOD DESCRIBED IN DOXSEY-WHITFIELD ET AL 2015 AND RASTERIZED AT 30-ARC-SECONDS HORIZONTAL RESOLUTION. ONE MAJOR ADVANTAGE OF THE GPW4 APPROACH TO DISAGGREGATING POPULATION ON THE BASIS OF UNIFORM AREAL DISTRIBUTION IS THAT THE FIDELITY OF THE INPUT INFORMATION IS MAINTAINED. ONE DISADVANTAGE TO THE GPW4 APPROACH IS THAT THE ACCURACY OF ANY GIVEN PIXEL IS PROPORTIONAL TO THE AVERAGE SIZE OF ITS INPUT VECTORS. THE AVERAGE SIZE OF INPUT VECTOR DATA VARIES ACROSS AND WITHIN COUNTRIES. WHERE INPUT VECTORS ARE OF COARSE RESOLUTION THE ACCURACY OF EACH UNDERLYING PIXEL MAY BE COMPROMISED.