People in Non - Urban Areas are Richer than those in Urban Areas ? A Comment to Ghosh

In environmental studies, different types of system boundaries are needed. Disaggregated GIS data are crucial because they can be flexibly converted into the target boundaries. The National Oceanic and Atmospheric Administration (NOAA) data of Gross Domestic Product (GDP) should be highly evaluated as a valuable GIS data. We, however, show the problem that GDP per capita in urban areas is lower than that in non-urban areas, based on the NOAA data of GDP. This is inconsistent with the fact derived from other relevant data. We discuss possible causes of the problem: continuous linear relationship between night-time lights and GDP; leakage effects of night-time lights from urban areas to their peripheral non-urban areas; excessive infrastructures in non-urban areas as compared with their economic output; and bias in the allocation of estimated GDP data in informal sectors. We would rather contribute to the potential correction of the data than criticize the data in this paper.