不限制随机样本
unrestricted random sample
未设限随机抽样
unrestricted random sampling
双无限随机环境
doubly infinite random environments
bi-infinite random environments
invariant measures
无机－无机复合粒子
in organic-inorganic composite particle
不可忽略的抽样机制
non-ignorable selection mechanism
按比例分层随机抽样
Proportion allocation in stratified random sampling
彼此独立的随机抽样法
Independent random sampling
不放回简单随机抽样
simple random sampling without replacement
成对的随机抽样法
Paired (or matched) random sampling
多阶段分层整群随机抽样
Multi-stage stratified cluster randomization
二段随机抽样
two-stage random sampling