Normalized First Street Census-Tract Data V1.3

Normalized 2020 and 2050 First Street flood risk data aggregated at the census-tract level. A lower number indicates less risk (0 is minimum) and a higher number indicates more risk (1 is maximum). The normalization process subtracts the mean from the local value and divides it by the standard deviation: ((tract_value - overall mean) / stand_dev). The overall mean is the national average of all census tracts. If you are interested in acquiring First Street flood data, you can request to access the data here. More information on First Street's flood risk statistics can be found here and information on First Street's hazards can be found here.

本数据集为已完成归一化处理的2020年与2050年First Street洪水风险数据，数据已按普查区块组（census-tract）级别进行聚合。数值越低代表风险程度越低（0代表最低风险），数值越高代表风险程度越高（1代表最高风险）。本次归一化处理的计算方式为：将单个普查区块组的本地数值减去整体均值，再除以标准差，具体计算公式为：(区块组数值 - 全国整体均值) / 标准差。其中，整体均值指全美国所有普查区块组的全国平均值。若您有意获取First Street洪水风险数据，可在此处申请数据访问权限。有关First Street洪水风险统计的更多详情可在此处查阅，有关First Street各类灾害的相关信息可在此处查阅。