Racial isolation values based on the 1990 census block group level using the 2010 census boundaries

These data contain a residential isolation value for non-Hispanic blacks (NHB) and non-Hispanic whites (NHW) at the census block group level. Population counts from the 1990 census using the 2010 census boundaries are used to calculate the index. For each block group, the index is the proportion of the population (NHB or NHW) in the index block group and block groups adjacent to the index block group. Islands (areal units with no first-level adjacent areal units) are removed as it is not possible to calculate isolation for units with no adjacent block groups.

本数据集涵盖普查街区组（census block group）尺度下的非西班牙裔黑人（non-Hispanic blacks, NHB）与非西班牙裔白人（non-Hispanic whites, NHW）居住隔离指数值。计算该指数所采用的人口计数数据源自1990年人口普查，并以2010年普查的地理边界作为统计基准。针对每个普查街区组，该指数为目标街区组及其相邻街区组内的（非西班牙裔黑人或非西班牙裔白人）人口占比。无一级相邻面状单元的孤岛（即不存在相邻街区组的面状单元）将被剔除，原因是无法为这类单元计算居住隔离指数。