CONCL USION: the calculation formulas of multiple - stratifying and clustering random sampling are theoretically set up.

结论：推导并建立多重分层、整群随机抽样误差的计算公式。

youdao

CONCL USION: the calculation formulas of multiple - stratifying and clustering random sampling are theoretically set up.

结论：推导并建立多重分层、整群随机抽样误差的计算公式。

youdao