“二阶抽样”的概念、定义、翻译、参考文献-科学参考

单词	二阶抽样
释义	二阶抽样 Encyclopedia 农学抽样调查释 two-stage sampling二阶抽样设总体由个初级单元组成，每个初级单元又由若干次级单元组成，在总体中按一定方法抽取若干初级单元，对每个被抽中的初级单元再抽取若干次级单元进行调查的方法。
随便看	Library Catalogue library catalogue Library Circulation Management library classification library clause of copyright law library cloud service library collection Library Collection Evaluation library consortia library cooperative system library copyright management library core values Library Council library culture library director library director's responsibility system library economics Library Education library education and research society of Chinese association for educational pronotion(CAEP) Library Ethics library evaluation library exhibition services Library for Children Library for Primary School Students library funds

科学参考收录了854744条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。