Firstly, we give an effective sampling design: a simple random case sample with replacement is drawn out of all cases; the control sample is drawn out of all controls with two-stage cluster sampling.
首先，我们设计了一个有效的抽样方案：采取简单随机抽样从病例组抽取样本；采取二阶段整群抽样从对照组抽取样本。
The Studies on Unit Root Test on Structural Changes Series with Small Samples Using GIBBS Sampler
具有结构突变的小样本GIBBS抽样单位根检验方法研究
The sampling shall be conducted by (two or more) professionals who have accepted special training, and the relevant personnel of the sampled entity shall be present at the scene.
抽样应当由受过专门培训的专业人员（二人以上）进行，被抽样单位的有关人员必须在场。
The Sampling Programme about Talent in Non-public Ownership System;
非公有制经济单位人才调查抽样设计
single random sampling
单次随机抽样 单次随机抽样
simple random sampling
简单随机抽样 简单随机抽样
When sampling, the personnel of the import entity and those of the customs shall be on the spot at the same time.
抽样时，进口单位和海关的人员应当同时在场。
Studies on the Sampling Methods for the Employees Survey in Small Economic Units;
小型经济单位从业人员调查抽样方法研究
Methods Investigate the medical staffs of sample hospital with survey forms.
方法对样本单位采用分层抽样方法进行问卷调查。
An applicant shall be responsible for the preparation of the tools and place for the sampling, and the move, stack transfer, opening and repackage, etc.
报验单位应当负责抽样所需工具和场地的准备，以及抽样时的搬移、倒垛、开拆和恢复包装等事项。
covariance for simple random sampling
简单随机抽样协方差
precision of simple random sampling
简单随机抽样精密度
Before sampling, the import entity shall provide the factory inspection report and the original origin certification.
进口单位应当在抽样前，提供出厂检验报告书和原产地证明原件。
Parameter Estimation Based on GEEs of the Data from Family-based Cluster Sampling;
以家庭为单位的整群抽样资料总体参数的GEE估计
A single unit, such as a pumping station, within such a system.
此系统中的单独单位，如抽水站
the port drug inspection office shall determine the methods jointly with the inspection application entity upon discussion in order to get representative samples.
口岸药品检验所应当与报验单位共同议定变更方法，以便抽取代表性样品。
Contrast group:Other 218 undergraduates were adopted in cluster sampling,taking class as unit.
对照组:除外观察组学生,随机在4届学生中以班为单位整群抽样218名学生。
A type of probability sample in which aggregations of sampling units, called clusters, are sampled at some stage in the process.
是一种将样本单元聚集在一起的随机抽样法.样本群在抽样的某一步骤被抽出.
Development of Systematic Sampling Dynamic Linkable Library with VB
VB实现简单随机抽样的DLL开发及应用