stratified random sampling

• 分层任意抽样,分层随机取土样,分层随机抽样

stratified random sampling的用法和样例：

例句

1. Method The sampling of individuals was done by the lamination random sampling.
   方法采用分层随机抽样法进行人群抽样，用改良加藤氏法粪检华支睾吸虫虫卵。