Gridded Population of the World, Version 4 (GPWv4): Population Density Adjusted to Match 2015 UN WPP Country Totals, Beta Release

The Gridded Population of the World, Version 4 (GPWv4) Population Density Adjusted to Match 2015 Revision of UN WPP Country Totals, Beta Release consists of estimates of human population density, based on counts consistent with national censuses and population registers with respect to relative spatial distribution, but adjusted to match the 2015 Revision of UN World Population Prospects country totals for the years 2000, 2005, 2010, 2015, and 2020.. A proportional allocation gridding algorithm, utilizing approximately 12.5 million national and sub-national administrative units, is used to assign population values to 30 arc-second (~1 km) grid cells. The population density grids are derived by dividing the population count grids by the land area grids. The pixel values represent persons per square kilometer.《世界栅格人口第四版（GPWv4）：适配联合国世界人口展望（UN World Population Prospects, UN WPP）2015修订版国家总人口的人口密度数据集（测试版）》包含人口密度估算结果：其基础人口计数符合国家级人口普查与人口登记的相对空间分布，并针对2000年、2005年、2010年、2015年及2020年，将人口数值调整至与UN WPP 2015修订版的国家总人口相匹配。本数据集采用比例分配栅格算法，依托约1250万个国家级及次级国家级行政单元，将人口数值赋值至30角秒（约1公里）的栅格单元。人口密度栅格由人口数量栅格除以土地面积栅格计算得到，其像素值代表每平方公里的人口数量。