Large-scale sample surveys are always undertaken with stratified multi-stage sampling.
大型抽样调查总是采用分层多阶段抽样。
Method:254 people aged 51~75 with two stage sampling were investigated by using multifactor analyses.
方法：采用二阶段抽样法对254名51～75岁居民用多因素分析法进行了调查分析。
This paper studies the second stage sampling methods used in the two stage sampling survey for waterway transportation volume.
研究了采用二阶抽样对水路运输量进行抽样调查时的第二阶抽样方法。
The distribution and quantity of Felis lynx population in the northeast have been found out by the three-stage sampling method.
我们利用三阶抽样法，查清了东北地区猞猁种群的分布及数量情况。
Methods 3-stage sampling was adopted to collect 15-69 year old constant inhabitants at sites of surveillance for questionnaire investigation.
方法采用3阶段抽样方法，抽取监测点15 ~ 69岁常住居民进行问卷调查。
A balanced three-layer sample rotation pattern is presented in this paper to solve the problem of rotation for the quarterly surveys with three-stage sampling designs.
本文构造了一种平衡的三层次样本轮换模式，解决了三阶段抽样季度调查的三层次样本轮换问题。
We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.
讨论多阶段抽样比率估计及其样本量选择的问题，给出了比率估计抽样均方误差的近似公式及其渐近无偏估计的公式。
We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.
讨论多阶段抽样比率估计及其样本量选择的问题，给出了比率估计抽样均方误差的近似公式及其渐近无偏估计的公式。
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