Before conducting regular sampling surveys, it is necessary to find out about the basic statistics units and their geographical distribution and to establish a scientific sampling framework in accordance with an approved plan for sampling surveys.
Before conducting regular sampling surveys, it is necessary to find out about the basic statistics units and their geographical distribution and to establish a scientific sampling framework in accordance with an approved plan for sampling surveys.
进行经常性抽样调查，应当在调查前查明基本统计单位及其分布情况，按照经批准的抽样调查方案，建立科学的抽样框。